econ-harvester-defense-raid: per-scenario chokepoint map

Replaces the generic rush-hour-arena base_map with a tailored
96x40 chokepoint-arena that funnels every raider through ONE
4-cell corridor at y=18..21. The water wall at x=46..54 splits
the map into a WEST lobe (agent base + harv + OFF-AXIS ore patch)
and an EAST lobe (raider spawn + persistent far-east enemy fact).

The single corridor mouth at (~44..46, 18..21) becomes the
canonical defensive position the model must read from the map
geometry. The off-axis patch keeps the harv commute strictly
inside the west lobe so the harv never touches the corridor,
which de-couples 'read the raid vector' from 'follow the harv'
and makes set_stance + position-the-escort-on-the-corridor-mouth
the load-bearing capability.

Hard tier keeps its two seed-driven AGENT spawn_point groups
(NORTH y=8 / SOUTH y=32) so the BASE moves but the corridor
mouth defensive position stays invariant.

Validation (scripted policies via openra_bench.eval_core.run_level):
stall (only observe) — LOSS every tier, seeds 1..2:
easy seed=1 loss / easy seed=2 loss
medium seed=1 loss / medium seed=2 loss
hard seed=1 loss / hard seed=2 loss
In every case the harv is killed (units_lost=1), confirming
the corridor + raider geometry still produces a real harv-death
LOSS rather than a draw.

Map spec (deterministic, content-addressed):
generator: chokepoint-arena, name: econ-harvester-defense-raid-arena
width: 96, height: 40, cordon: 2
pinch_x: 50, pinch_width: 8, corridor_width: 4, corridor_y: 20

openra_bench/scenarios/packs/econ-harvester-defense-raid.yaml

@@ -11,14 +11,39 @@
 # The load-bearing verb is `set_stance(escort, 2 or 3)` + escort
 # movement onto the harv's lane.
 #
+# MAP — econ-harvester-defense-raid-arena (96×40 chokepoint-arena)
+# ----------------------------------------------------------------
+# Per-scenario map (replaces the generic rush-hour-arena). A single
+# vertical water wall at x=46..54 with one open corridor at y=18..21
+# splits the playable area into a WEST lobe (the agent's base + the
+# harv + the off-axis ore patch) and an EAST lobe (the raider spawn
+# axis + the persistent far-east enemy fact). The corridor at
+# y=18..21 is the ONE lane any raid wave must use to cross from the
+# east into the west lobe — there is no other route around the wall.
+#
+# The ore patch sits OFF-AXIS from the agent base (easy/medium: base
+# at y=10..14, patch at y=28; hard NORTH: base at y=8, patch at
+# y=12; hard SOUTH: base at y=32, patch at y=28). Off-axis means the
+# harv commutes between proc and mine on a y-band that is NOT the
+# raid corridor's y-band — so the agent can read the raid vector
+# (the single corridor mouth at the west wall, x≈44..46, y=18..21)
+# INDEPENDENTLY of where its own harv currently is, and plant the
+# defense on that one lane.
+#
+# This is what the scenario MEASURES: reading the raid vector from
+# the map geometry (one corridor, one mouth) and positioning the
+# escort there — not spamming defense everywhere or following the
+# harv around. set_stance + escort movement onto the corridor mouth
+# is the load-bearing capability the chokepoint exposes.
+#
 # DESIGN
 # ------
 # Agent has fact + powr + proc + 1× harv + ONE NEAR ore patch (mine
-# at x=25). The proc seeds the harv's auto-harvest loop (per
-# world.rs::auto_route_idle_harvesters — a scenario-placed idle harv
-# auto-routes once its owner owns a refinery), so the harv cycles
-# proc(12,20) ↔ mine(25,20) WITHOUT an explicit harvest order. Income
-# is steady AS LONG AS THE HARV LIVES.
+# OFF-AXIS from the base). The proc seeds the harv's auto-harvest
+# loop (per world.rs::auto_route_idle_harvesters — a scenario-placed
+# idle harv auto-routes once its owner owns a refinery), so the harv
+# cycles proc ↔ mine WITHOUT an explicit harvest order. Income is
+# steady AS LONG AS THE HARV LIVES.
 #
 # Threat: enemy `bot_type: raider` (openra-sim/src/scripted_bot.rs:
 # ScriptedBehavior::Raider) — its tick() picks the agent's harv
@@ -26,55 +51,59 @@
 # one every 12 ticks (the raider interval). New units added to the
 # raider's roster (via scheduled_events::spawn_actors) are picked up
 # on the next own_mobile() scan, so SCHEDULED raid waves all chase
-# the harv.
+# the harv. Because the wall blocks every other east→west route,
+# each spawned raider MUST enter the west lobe through the single
+# corridor at (~50, 18..21).
 #
 # Wave schedule (scheduled_events: spawn_actors):
-#   easy:   1 wave  — 1× 2tnk at tick 600   from (40,20)
-#   medium: 2 waves — 1× 2tnk at tick 600, 1× 2tnk at tick 1500 — both at (40,20)
-#   hard:   3 waves on 2 seed-driven axes — see hard tier comment
+#   easy:   1 wave  — 1× 2tnk at tick 600   from (75,20)
+#   medium: 2 waves — 1× 2tnk at tick 600, 1× 2tnk at tick 1500 — both at (75,20)
+#   hard:   3 waves on the central east corridor — see hard tier comment
 #
 # Escort: 2× 2tnk at base, stance:0 (HoldFire). The escort SITS at
 # the proc; even when a raider walks into its weapon range the
 # stance:0 units do not fire (verified per CLAUDE.md stance fix:
 # stance:0 never auto-engages, even when shot at, even when an enemy
 # is sitting on top of them). The agent must EITHER:
-#   (a) `set_stance(escort, 3)` — Hunt: idle escort actively advances
-#       on visible enemies (raider walks into LOS as it approaches
-#       the harv's lane, escort engages); OR
-#   (b) `set_stance(escort, 2)` AND `attack_move(escort, raider lane)`
-#       — Defend stance auto-fires on whatever enters weapon range,
-#       so move the escort east along the harv's commute axis to
-#       INTERCEPT the raid wave; OR
+#   (a) `set_stance(escort, 3)` and move them onto the corridor
+#       mouth — Hunt: idle escort actively advances on visible
+#       enemies (raider walks into LOS as it exits the corridor,
+#       escort engages); OR
+#   (b) `set_stance(escort, 2)` AND `attack_move(escort, corridor
+#       mouth)` — Defend stance auto-fires on whatever enters weapon
+#       range, so move the escort EAST onto the west mouth of the
+#       corridor (x≈44..46, y=18..21) to INTERCEPT the raid wave; OR
 #   (c) `attack_unit(escort, raider_id)` — explicit order overrides
 #       stance:0, escort closes and kills the raider.
 # Any of (a), (b), (c) clears the bar. The capability is "flip the
-# escort from passive to active" — same verb as combat-tanya-vs-rush.
+# escort from passive to active AND plant it on the corridor mouth"
+# — same verb as combat-tanya-vs-rush plus a positioning read.
 #
 # THE NO-CHEAT BAR (every lazy / stall / wrong-shape policy LOSES on
 # every level and every hard seed; the intended capability WINS):
 #
 #   • stall (only observe): escort stays stance:0 at base, never
-#     engages. Raider wave 1 reaches the harv around tick ~750
-#     (40→16 ≈ 24 cells at 2tnk speed) and kills it. unit_type_count_gte
-#     :{harv,1} fails → fail_condition fires → LOSS.
+#     engages. Raider wave 1 traverses the corridor, detours to the
+#     active harv latitude and kills it. unit_type_count_gte:
+#     {harv,1} fails → fail_condition fires → LOSS.
 #
 #   • defensive-but-passive (place / re-issue HoldFire on escort,
 #     observe): identical outcome — the escort is structurally
 #     incapable of engaging. Harv dies → LOSS.
 #
-#   • aggressive-but-no-escort (send escort east to the raider's
-#     spawn point at x=40, leaving harv alone on the lane between
-#     proc(12,20) and mine(25,20)): the escort marches AROUND or
-#     PAST the next raid wave, the wave reaches the undefended harv,
-#     harv dies → LOSS. (On easy with one wave the escort might
-#     catch the lone raider, but on medium/hard, the second/third
-#     wave finds the harv unprotected because the escort overshot.)
+#   • spam-defense-everywhere (escort split across the base
+#     perimeter, neither piece on the corridor mouth): the raider
+#     walks straight through the corridor on the same lane every
+#     wave; whichever escort piece is on the wrong band never
+#     contributes. On medium/hard the second/third wave finishes
+#     the harv → LOSS.
 #
 #   • intended (set_stance(escort, 2 or 3) and/or attack_move escort
-#     onto the harv's lane ~x=20..25): raider walks into the escort's
-#     fire envelope on its approach, escort kills the raid wave
-#     before contact with the harv, harv survives, auto-route loop
-#     continues, cash bar clears → WIN.
+#     onto the corridor mouth ~x=44..46, y=18..21): the wall geometry
+#     forces every raider through the escort's fire envelope on its
+#     approach, escort kills each raid wave before contact with the
+#     harv, harv survives, auto-route loop continues, cash bar
+#     clears → WIN.
 #
 # ENGINE FACTS (CLAUDE.md):
 #   - Tick budget ~90/turn. easy max_turns=35 ⇒ ceiling 93+90·34=3153;
@@ -97,21 +126,24 @@
 #     intended path; the load-bearing verb is the stance flip OR
 #     an explicit attack order (which overrides stance per the
 #     CLAUDE.md stance fix).
-#   - Persistent far enemy `fact` at (120,20) — anti-DRAW per
-#     CLAUDE.md (engine auto-`done`s on enemy-elim before win/fail
-#     evaluates; the inert far marker keeps the episode alive past
-#     the raider being destroyed).
+#   - Persistent far enemy `fact` at (90,20) in the EAST lobe —
+#     anti-DRAW per CLAUDE.md (engine auto-`done`s on enemy-elim
+#     before win/fail evaluates; the inert far marker keeps the
+#     episode alive past the raider being destroyed). The wall
+#     prevents agent units from reaching it without crossing the
+#     corridor, so an intended-defense play does not incidentally
+#     destroy the marker.
 #   - `unit_type_count_gte: {harv, 1}` in fail_condition is the
 #     hard harv-survival predicate — the moment the harv dies the
 #     fail clause fires and the LOSS is immediate.
-#   - hard tier uses TWO seed-driven SCHEDULED_EVENTS spawn AXES
-#     (raid approaches from the north vs the south of the harv's
-#     lane). The `spawn_actors` event itself doesn't honour
-#     spawn_point, so per-seed axis variation is done by giving
-#     each seed group a distinct AGENT spawn_point — the active
-#     base latitude (y=14 vs y=26) determines which raid lane is
-#     "the harv's lane". This satisfies the ≥2-distinct-seed-driven-
-#     spawn-groups hard-tier requirement (CLAUDE.md §7).
+#   - hard tier uses TWO seed-driven AGENT spawn_point groups (base
+#     latitude NORTH y=8 vs SOUTH y=32). Each group has its own
+#     fact/powr/proc/harv/escort + mine on its own y-band. The
+#     load-bearing decision is the same (flip + position escort on
+#     the corridor mouth) but the LATITUDE of the base varies per
+#     seed, so a memorised opening from the wrong latitude leaves
+#     the harv unprotected. This satisfies the ≥2-distinct-seed-
+#     driven-spawn-groups hard-tier requirement (CLAUDE.md §7).
 #
 # Validate (no model / no network):
 #   python3 -m openra_bench.scenarios.validate \
@@ -131,25 +163,35 @@ meta:
     decision is to FLIP the escort from passive to active — set its
     stance to defend / attack-anything, or order it onto the
     harvester's lane to intercept — so the raider dies on the
-    escort's fire envelope before reaching the harvester. Stalling
-    or leaving the escort on hold-fire lets every wave through; the
-    harvester dies, income stops, the cash bar is unmet.
+    escort's fire envelope before reaching the harvester. The map
+    geometry funnels every raider through a single corridor mouth,
+    so the right place to plant the escort is unambiguous if the
+    agent reads the map. Stalling, leaving the escort on hold-fire,
+    or spreading defense everywhere instead of on the corridor mouth
+    all let the harvester die.
   robotics_analogue: >
     Mining-fleet protection under recurring asset-targeted attack —
     an autonomous extraction site with an extractor robot, a
     processing depot, and a static defense detail. If the defense
     detail is in safe-mode (hold fire) the recurring attacker
     destroys the extractor on the first cycle; the operator must
-    flip the detail to engage and (optionally) reposition it onto
-    the extractor's commute lane.
+    flip the detail to engage and reposition it onto the single
+    access route the attacker must use.
   benchmark_anchor:
     - "SC2 harvester harass defense (Lambo, Reaper drops on workers)"
     - "convoy / extractor protection under recurring harass"
     - "RTS stance management — flip escort from passive to active"
     - "SOC active-vs-passive monitoring posture"
+    - "chokepoint defense — plant the line on the one route"
   author: openra-bench
 
-base_map: rush-hour-arena
+# Per-scenario map: chokepoint-arena 96×40 with a vertical water wall
+# at x=46..54 broken by a single 4-cell corridor at y=18..21. The
+# corridor is the ONE lane any raider must use to cross from the east
+# raid-spawn lobe into the west base/patch lobe. Top-level base_map
+# is the readable slug; each level's overrides: re-declares the full
+# generator spec so materialize() builds the .oramap deterministically.
+base_map: econ-harvester-defense-raid-arena
 starting_cash: 0  # ALL income via harv survival; bar measures live throughput.
 
 base:
@@ -175,73 +217,91 @@ base:
 
 levels:
   # ── EASY ─────────────────────────────────────────────────────────
-  # Bare skill: ONE raid wave (1× 2tnk) at tick 600. Harv cycles
-  # proc(12,20)↔mine(25,20) on auto-route. Escort: 2× 2tnk at base
-  # stance:0. Stall / passive: raider reaches harv ~tick 750, harv
-  # dies, LOSS. Intended: set_stance(escort, 2 or 3) and/or
-  # attack_move escort east to ~x=20, escort engages the raider on
-  # approach, harv survives, cash accumulates from auto-harvest.
-  # Bar: cash >= 800 (~2 refines × ~400cr) before tick 3000.
+  # Bare skill: ONE raid wave (1× 2tnk) at tick 600 from (75,20) in
+  # the EAST lobe. Harv cycles proc(10,12)↔mine(30,28) on auto-route
+  # entirely inside the WEST lobe. Escort: 2× 2tnk at base stance:0.
+  # Stall / passive: raider crosses the corridor (only route), detours
+  # south to the harv on its commute and kills it → LOSS. Intended:
+  # set_stance(escort, 2 or 3) and/or attack_move escort east to the
+  # west corridor mouth (~x=44..46, y=18..21); escort engages every
+  # raider on exit from the corridor, harv survives, cash accumulates.
+  # Bar: cash >= 1200 before tick 3000.
   # max_turns 35 ⇒ ceiling 93+90·34=3153 > 3001 ✓.
   easy:
     description: >
-      You own a Construction Yard, Power Plant, Refinery, ONE Ore
-      Truck on auto-harvest to the near patch at (25,20), and TWO
-      medium tanks (2tnk) parked at your refinery on HOLD-FIRE
-      stance. At tick 600 an enemy raider tank spawns at (40,20)
-      and drives STRAIGHT at your harvester (the raider bot targets
-      harvesters specifically). Win when cash >= 800 AND your
-      harvester is still alive AND your refinery is intact, before
-      tick 3000. Standing the escort idle (HOLD-FIRE) lets the
-      raider walk through and kill the harvester. The intended play
-      is to FLIP the escort's stance to Defend (2) or AttackAnything
-      (3), OR explicitly attack-order it onto the raider's approach
-      lane.
+      You own a Construction Yard, Power Plant, Refinery (NW corner,
+      around y=10..12), ONE Ore Truck on auto-harvest to an
+      OFF-AXIS ore patch SOUTH of base at (30,28), and TWO medium
+      tanks (2tnk) parked at your refinery on HOLD-FIRE stance.
+      A vertical water wall at x=46..54 splits the map; the ONLY
+      crossing is a 4-cell corridor at y=18..21. At tick 600 an
+      enemy raider tank spawns at (75,20) in the eastern lobe and
+      drives at your harvester — it MUST come through the corridor
+      to reach you. Win when cash >= 1200 AND your harvester is
+      still alive AND your refinery is intact, before tick 3000.
+      Standing the escort idle (HOLD-FIRE) at base lets the raider
+      walk through and kill the harvester. The intended play is to
+      FLIP the escort's stance to Defend (2) or AttackAnything (3)
+      AND move it onto the west corridor mouth (around x=44..46,
+      y=18..21) so the raider dies on its way out of the corridor.
     starting_cash: 0
     overrides:
+      base_map:
+        generator: chokepoint-arena
+        name: econ-harvester-defense-raid-arena
+        width: 96
+        height: 40
+        cordon: 2
+        pinch_x: 50
+        pinch_width: 8
+        corridor_width: 4
+        corridor_y: 20
       actors:
-        # Agent base — fact + powr seed the construction & power;
-        # proc seeds the harv auto-harvest loop.
-        - {type: fact, owner: agent, position: [10, 20]}
-        - {type: powr, owner: agent, position: [10, 18]}
-        - {type: proc, owner: agent, position: [12, 20]}
+        # Agent base — NW corner; fact + powr seed the construction
+        # & power; proc seeds the harv auto-harvest loop.
+        - {type: fact, owner: agent, position: [8, 10]}
+        - {type: powr, owner: agent, position: [8, 8]}
+        - {type: proc, owner: agent, position: [10, 12]}
         # Single harv — pre-placed adjacent to proc. With proc on the
         # field, world.rs::auto_route_idle_harvesters installs a
         # Harvest activity on the next tick; harv cycles proc<->mine.
-        - {type: harv, owner: agent, position: [14, 20]}
+        - {type: harv, owner: agent, position: [12, 12]}
         # Escort: 2× 2tnk at the proc on stance:0 (HoldFire). The
-        # capability under test is "flip the escort active" — stance:0
-        # never auto-engages, so a "place defenders and observe"
-        # policy LOSES.
-        - {type: 2tnk, owner: agent, position: [13, 18], stance: 0}
-        - {type: 2tnk, owner: agent, position: [13, 22], stance: 0}
-        # Near ore patch — the harv's auto-route target.
-        - {type: mine, owner: neutral, position: [25, 20]}
-        # Persistent far enemy fact — anti-DRAW (engine auto-done
-        # mitigation; without this the run collapses to DRAW the
-        # instant the raid wave is destroyed, before the cash bar
-        # evaluates).
-        - {type: fact, owner: enemy, position: [120, 20]}
+        # capability under test is "flip the escort active AND
+        # position it on the corridor mouth" — stance:0 never auto-
+        # engages, and a "place defenders at base and observe"
+        # policy LOSES because the corridor is too far east for
+        # base-bound defenders to fire on.
+        - {type: 2tnk, owner: agent, position: [14, 12], stance: 0}
+        - {type: 2tnk, owner: agent, position: [14, 14], stance: 0}
+        # OFF-AXIS ore patch — south of base; the harv's auto-route
+        # target. Diagonal commute proc(10,12)↔mine(30,28) stays
+        # entirely in the WEST lobe (x<46), so the harv never
+        # touches the corridor.
+        - {type: mine, owner: neutral, position: [30, 28]}
+        # Persistent far enemy fact — east lobe, anti-DRAW (engine
+        # auto-done mitigation). Behind the wall and reachable only
+        # via the corridor, so an intended defense play does not
+        # incidentally destroy the marker.
+        - {type: fact, owner: enemy, position: [90, 20]}
       scheduled_events:
-        # Single raid wave at tick 600 — one 2tnk spawned east of
-        # the patch. Under bot_type:raider the new tank joins the
-        # raider's own_mobile() roster on the next tick and beelines
-        # toward the harv via harv_foes().
+        # Single raid wave at tick 600 — one 2tnk spawned in the
+        # east lobe. The raider bot's harv_foes() picks the agent's
+        # harv; the wall forces the approach through the corridor.
         - tick: 600
           type: spawn_actors
           actors:
-            - {type: 2tnk, owner: enemy, position: [40, 20]}
+            - {type: 2tnk, owner: enemy, position: [75, 20]}
     win_condition:
       # Ordered `then:` enforces "harv must SURVIVE past the raid
       # window and THEN keep refining to the bar" — clause 1
       # (after_ticks: 1700) latches only past wave 1's typical
-      # kill-window (raider spawns tick 600, reaches harv ~tick 900,
-      # kills undefended harv by ~tick 1500). A stall run loses its
-      # harv around tick ~1500 so by the time clause 1 latches the
-      # `unit_type_count_gte:{harv,1}` clause has already failed →
-      # fail_condition fires first. The intended escort engagement
-      # kills the raider, harv keeps cycling, cash crosses 1200
-      # well after tick 1700, all_of latches → WIN.
+      # kill-window. A stall run loses its harv well before clause 1
+      # latches; the `unit_type_count_gte:{harv,1}` clause has
+      # already failed → fail_condition fires first. The intended
+      # escort engagement at the corridor mouth kills each raider,
+      # harv keeps cycling, cash crosses 1200 well after tick 1700,
+      # all_of latches → WIN.
       all_of:
         - then:
             id: econ-harvester-defense-raid-easy
@@ -260,52 +320,64 @@ levels:
 
   # ── MEDIUM ───────────────────────────────────────────────────────
   # +1 controlled variable: TWO raid waves (tick 600, tick 1500) and
-  # a tighter bar (cash >= 1600 ≈ 4 refines). A one-time "kill the
-  # first raider" play has to ALSO survive the second wave — the
-  # escort must be RETURNED to a covering position (or kept on
-  # AttackAnything stance:3) so the late wave dies on approach too.
+  # a tighter bar (cash >= 2200 ≈ 5..6 refines). A one-time "kill the
+  # first raider" play has to ALSO hold the corridor against the
+  # second wave — the escort must be RETURNED to (or kept on) the
+  # corridor mouth (or kept on AttackAnything stance:3) so the late
+  # wave dies on approach too.
   # max_turns 45 ⇒ ceiling 4053 > 3901 ✓.
   medium:
     description: >
-      Same setup as easy — fact + powr + proc + 1× harv on auto-harvest to the near patch at (25,20), 2× 2tnk escort at the
-      refinery on HOLD-FIRE — but TWO raider waves arrive: one at
-      tick 600 and a second at tick 1500. Both spawn at (40,20) and
-      drive at your harvester. Win when cash >= 1600 AND your
-      harvester is alive AND your refinery is intact, before tick
-      3900. Stalling, leaving the escort on hold-fire, and chasing
-      the first raider far enough east to miss the second wave all
-      LOSE. The intended play is to flip the escort active (stance
-      Defend or AttackAnything) and position it on the harvester's
-      lane so BOTH waves die on approach.
+      Same setup as easy — fact + powr + proc + 1× harv on
+      auto-harvest to the OFF-AXIS patch at (30,28), 2× 2tnk escort
+      at the refinery on HOLD-FIRE, same chokepoint map — but TWO
+      raider waves arrive: one at tick 600 and a second at tick 1500.
+      Both spawn at (75,20) in the eastern lobe and must cross the
+      single corridor (y=18..21) to reach your harvester. Win when
+      cash >= 2200 AND your harvester is alive AND your refinery is
+      intact, before tick 3900. Stalling, leaving the escort on
+      hold-fire, and chasing the first raider PAST the corridor far
+      enough to miss the second wave all LOSE. The intended play is
+      to flip the escort active (stance Defend or AttackAnything)
+      and HOLD the corridor mouth so BOTH waves die on approach.
     starting_cash: 0
     overrides:
+      base_map:
+        generator: chokepoint-arena
+        name: econ-harvester-defense-raid-arena
+        width: 96
+        height: 40
+        cordon: 2
+        pinch_x: 50
+        pinch_width: 8
+        corridor_width: 4
+        corridor_y: 20
       actors:
-        - {type: fact, owner: agent, position: [10, 20]}
-        - {type: powr, owner: agent, position: [10, 18]}
-        - {type: proc, owner: agent, position: [12, 20]}
-        - {type: harv, owner: agent, position: [14, 20]}
-        - {type: 2tnk, owner: agent, position: [13, 18], stance: 0}
-        - {type: 2tnk, owner: agent, position: [13, 22], stance: 0}
-        - {type: mine, owner: neutral, position: [25, 20]}
-        - {type: fact, owner: enemy, position: [120, 20]}
+        - {type: fact, owner: agent, position: [8, 10]}
+        - {type: powr, owner: agent, position: [8, 8]}
+        - {type: proc, owner: agent, position: [10, 12]}
+        - {type: harv, owner: agent, position: [12, 12]}
+        - {type: 2tnk, owner: agent, position: [14, 12], stance: 0}
+        - {type: 2tnk, owner: agent, position: [14, 14], stance: 0}
+        - {type: mine, owner: neutral, position: [30, 28]}
+        - {type: fact, owner: enemy, position: [90, 20]}
       scheduled_events:
         - tick: 600
           type: spawn_actors
           actors:
-            - {type: 2tnk, owner: enemy, position: [40, 20]}
+            - {type: 2tnk, owner: enemy, position: [75, 20]}
         - tick: 1500
           type: spawn_actors
           actors:
-            - {type: 2tnk, owner: enemy, position: [40, 20]}
+            - {type: 2tnk, owner: enemy, position: [75, 20]}
     win_condition:
-      # `then:` forces cash bar to be reached AFTER tick 2700 —
-      # past the second raid wave's kill-window (wave 2 spawns at
-      # tick 1500, reaches harv ~tick 1800, kills undefended harv
-      # by ~tick 2400). Aggressive-no-escort (drive escort east
-      # past patch) lets wave 1 chip the harv heavily AND wave 2
-      # finish it; the harv dies before clause 1 latches → fail
-      # clause unit_type_count_gte:{harv,1} fires → LOSS even
-      # though enough cash may have accumulated by ~tick 2200.
+      # `then:` forces cash bar to be reached AFTER tick 2700 — past
+      # the second raid wave's kill-window (wave 2 spawns at tick
+      # 1500, reaches harv ~tick 2000, kills undefended harv by
+      # ~tick 2600). Aggressive-no-corridor-hold (drive escort
+      # east past the corridor) lets wave 1 chip the harv and wave
+      # 2 finish it; the harv dies before clause 1 latches → fail
+      # clause unit_type_count_gte:{harv,1} fires → LOSS.
       all_of:
         - then:
             id: econ-harvester-defense-raid-medium
@@ -324,103 +396,122 @@ levels:
 
   # ── HARD ─────────────────────────────────────────────────────────
   # +1 axis vs medium: TWO seed-driven AGENT spawn_point groups —
-  # base latitude NORTH y=14 vs SOUTH y=26, round-robined per seed.
+  # base latitude NORTH y=8 vs SOUTH y=32, round-robined per seed.
   # Each group has its own fact/powr/proc/harv/escort/mine on its
-  # own y-band. The agent's load-bearing decision is the same
-  # (flip + position escort) but the LATITUDE varies per seed, so
-  # a memorised y=20 opening fails on both hard seed groups.
+  # own y-band, ENTIRELY inside the west lobe (above the corridor
+  # for NORTH, below for SOUTH). The agent's load-bearing decision
+  # is the same (flip + position escort onto the corridor mouth)
+  # but the harv's latitude varies per seed, so a memorised opening
+  # that ignores the active base latitude leaves the harv exposed
+  # on the wrong y after the raider exits the corridor.
   #
   # Hard tier ≥2-spawn-groups requirement (CLAUDE.md §7): satisfied
   # via two AGENT spawn_point groups (spawn_point: 0 / 1) — every
   # agent actor is duplicated across both groups; the active group
   # is round-robined by seed.
   #
-  # Three raid waves (ticks 600, 1500, 2400) spawn ON A CENTRAL
-  # AXIS at y=20 (between the two possible latitudes — like
-  # econ-protect-harvester-route's hard tier). The raider bot
-  # targets the agent's on-latitude harv, so each raider must
-  # detour to y=14 or y=26 (a 5-6 cell extra leg) on top of its
-  # west-bound traversal. The detour gives the escort time to
-  # intercept the raider on the agent's own y-band. The escort
-  # MUST be moved onto the agent's latitude — a memorised "send
-  # escort east on y=20" opening drops them onto a lane the raider
-  # only briefly crosses, while the harv on y=14/26 is unprotected
-  # for the rest of the raider's approach.
+  # Three raid waves (ticks 600, 1500, 2400) spawn on the central
+  # east axis at (75,20). Per the raider bot, each one targets the
+  # active harv; the wall forces every approach through the
+  # corridor (y=18..21), then the raider detours north or south to
+  # the active harv latitude (NORTH y=8 needs a ~10-cell detour
+  # north of the corridor; SOUTH y=32 needs a ~11-cell detour
+  # south). The corridor mouth (x≈44..46, y=18..21) is the SHARED
+  # defensive position for BOTH spawn groups, so the load-bearing
+  # capability — read the corridor + plant escort there — is
+  # invariant across seeds; only the escort's STARTING position
+  # changes (north base vs south base).
   # max_turns 50 ⇒ ceiling 4503 > 4301 ✓.
   hard:
     description: >
-      Tougher version: your base latitude varies per seed — NORTH
-      base (y=14) OR SOUTH base (y=26). Each base has its own fact,
-      powr, proc, harvester on auto-harvest to its OWN near patch
-      (mine at (25,14) for NORTH; mine at (25,26) for SOUTH), and
-      2× 2tnk escort at the refinery on HOLD-FIRE. THREE raider
-      heavy tanks arrive at ticks 600, 1500, and 2400 from the
-      central east corridor at (40,20); each one detours north or
-      south to your harvester's latitude. Win when cash >= 2800
-      AND your harvester is alive AND your refinery is intact,
-      before tick 4300. Stalling, leaving escort on hold-fire,
-      chasing past the lane, and memorising the wrong latitude all
-      LOSE. Flip the escort to Defend / AttackAnything (or attack-order it onto your harvester's lane) so all three waves die
-      on approach.
+      Tougher version on the same chokepoint map: your base
+      latitude varies per seed — NORTH base (y=8) OR SOUTH base
+      (y=32). Each base has its own fact, powr, proc, harvester on
+      auto-harvest to its OWN OFF-AXIS near patch (mine at (30,12)
+      for NORTH; mine at (30,28) for SOUTH), and 2× 2tnk escort at
+      the refinery on HOLD-FIRE. THREE raider heavy tanks arrive
+      at ticks 600, 1500, and 2400 from the central east corridor
+      at (75,20); each one drives through the single corridor at
+      y=18..21 then detours to your harvester's latitude. Win when
+      cash >= 2800 AND your harvester is alive AND your refinery
+      is intact, before tick 4300. Stalling, leaving escort on
+      hold-fire, parking escort at base, and missing the corridor
+      mouth all LOSE. Flip the escort to Defend / AttackAnything
+      AND attack-move it onto the corridor mouth (around x=44..46,
+      y=18..21) so all three waves die on approach.
     starting_cash: 0
     overrides:
+      base_map:
+        generator: chokepoint-arena
+        name: econ-harvester-defense-raid-arena
+        width: 96
+        height: 40
+        cordon: 2
+        pinch_x: 50
+        pinch_width: 8
+        corridor_width: 4
+        corridor_y: 20
       actors:
-        # spawn_point 0 — NORTH base (y=14). CLAUDE.md: agent actors
+        # spawn_point 0 — NORTH base (y=8). CLAUDE.md: agent actors
         # must be duplicated across both spawn_point groups (the
         # filter drops any group-untagged actor on either side).
-        - {type: fact, owner: agent, position: [10, 14], spawn_point: 0}
-        - {type: powr, owner: agent, position: [8, 12], spawn_point: 0}
-        - {type: proc, owner: agent, position: [12, 14], spawn_point: 0}
-        - {type: harv, owner: agent, position: [14, 14], spawn_point: 0}
+        - {type: fact, owner: agent, position: [8, 8], spawn_point: 0}
+        - {type: powr, owner: agent, position: [8, 6], spawn_point: 0}
+        - {type: proc, owner: agent, position: [10, 8], spawn_point: 0}
+        - {type: harv, owner: agent, position: [12, 8], spawn_point: 0}
         # Escort placed on open ground east of the proc so attack_move
-        # has a clear east lane (no powr or building footprint to
-        # path around).
-        - {type: 2tnk, owner: agent, position: [15, 13], stance: 0, spawn_point: 0}
-        - {type: 2tnk, owner: agent, position: [15, 15], stance: 0, spawn_point: 0}
-        # spawn_point 1 — SOUTH base (y=26). Symmetric.
-        - {type: fact, owner: agent, position: [10, 26], spawn_point: 1}
-        - {type: powr, owner: agent, position: [8, 28], spawn_point: 1}
-        - {type: proc, owner: agent, position: [12, 26], spawn_point: 1}
-        - {type: harv, owner: agent, position: [14, 26], spawn_point: 1}
-        - {type: 2tnk, owner: agent, position: [15, 25], stance: 0, spawn_point: 1}
-        - {type: 2tnk, owner: agent, position: [15, 27], stance: 0, spawn_point: 1}
-        # Two ore patches — one per latitude. Mines are neutral, so
-        # the spawn_point filter (agent-side) does not affect them;
-        # both place every seed. The active harv only uses ITS OWN
-        # patch (auto-route picks the nearest ore the owner can
-        # reach, which on each seed is the on-latitude one).
-        - {type: mine, owner: neutral, position: [25, 14]}
-        - {type: mine, owner: neutral, position: [25, 26]}
-        # Persistent far enemy fact — anti-DRAW.
-        - {type: fact, owner: enemy, position: [120, 20]}
+        # has a clear east lane to the corridor mouth.
+        - {type: 2tnk, owner: agent, position: [14, 7], stance: 0, spawn_point: 0}
+        - {type: 2tnk, owner: agent, position: [14, 9], stance: 0, spawn_point: 0}
+        # spawn_point 1 — SOUTH base (y=32). Symmetric.
+        - {type: fact, owner: agent, position: [8, 32], spawn_point: 1}
+        - {type: powr, owner: agent, position: [8, 34], spawn_point: 1}
+        - {type: proc, owner: agent, position: [10, 32], spawn_point: 1}
+        - {type: harv, owner: agent, position: [12, 32], spawn_point: 1}
+        - {type: 2tnk, owner: agent, position: [14, 31], stance: 0, spawn_point: 1}
+        - {type: 2tnk, owner: agent, position: [14, 33], stance: 0, spawn_point: 1}
+        # Two ore patches — one per latitude, BOTH entirely in the
+        # west lobe (x<46) and on their respective sides of the
+        # corridor. Mines are neutral, so the spawn_point filter
+        # (agent-side) does not affect them; both place every seed.
+        # The active harv only uses ITS OWN patch (auto-route picks
+        # the nearest ore the owner can reach, which on each seed
+        # is the on-latitude one).
+        - {type: mine, owner: neutral, position: [30, 12]}
+        - {type: mine, owner: neutral, position: [30, 28]}
+        # Persistent far enemy fact — east lobe, anti-DRAW.
+        - {type: fact, owner: enemy, position: [90, 20]}
       scheduled_events:
-        # Three raid waves spawn on a CENTRAL corridor at y=20 (per
-        # econ-protect-harvester-route's hard idiom). Each raider is
-        # bot-controlled and detours 6 cells north/south to reach the
-        # on-latitude harv — the detour gives the escort time to
-        # intercept on the agent's own y-band. The escort MUST land
-        # on the agent's latitude; memorising the y=20 corridor
-        # leaves the harv unprotected for the bulk of the raider's
-        # approach lane.
+        # Three raid waves spawn on the central east corridor axis
+        # at (75,20). Each raider is bot-controlled and must traverse
+        # the single corridor (y=18..21) — the wall blocks every
+        # other east→west route — then detour ~10-11 cells north or
+        # south to reach the on-latitude harv. The detour gives the
+        # escort time to intercept at the corridor mouth, but ONLY
+        # if the escort is actually parked there. A memorised
+        # "send escort east along base latitude" opening drops them
+        # at y=8 (NORTH) or y=32 (SOUTH), well off the corridor;
+        # the raider exits the corridor unopposed and reaches the
+        # harv unmolested.
         - tick: 600
           type: spawn_actors
           actors:
-            - {type: 2tnk, owner: enemy, position: [40, 20]}
+            - {type: 2tnk, owner: enemy, position: [75, 20]}
         - tick: 1500
           type: spawn_actors
           actors:
-            - {type: 2tnk, owner: enemy, position: [40, 20]}
+            - {type: 2tnk, owner: enemy, position: [75, 20]}
         - tick: 2400
           type: spawn_actors
           actors:
-            - {type: 2tnk, owner: enemy, position: [40, 20]}
+            - {type: 2tnk, owner: enemy, position: [75, 20]}
     win_condition:
       # `then:` forces cash bar AFTER tick 3500 — past wave 3
-      # (spawns tick 2400, reaches harv ~tick 2700, kills
-      # undefended harv by ~tick 3300). Stall / passive / off-axis
+      # (spawns tick 2400, reaches harv ~tick 2900, kills
+      # undefended harv by ~tick 3400). Stall / passive / off-axis
       # all lose their harv before tick 3500 → unit_type_count_gte
-      # fail clause fires → LOSS. Intended (escort on harv's
-      # latitude) kills each wave on approach; harv cycles
+      # fail clause fires → LOSS. Intended (escort planted on the
+      # corridor mouth) kills each wave on approach; harv cycles
       # uninterrupted through all three waves and accumulates
       # cash past tick 3500.
       all_of: