platformer: asset-expansion Phases D + E (defeat juice, snakes, lava serpent)

CHANGELOG.md

@@ -10,6 +10,63 @@ The native shim's ABI is tracked separately by `b2Version()` (currently `4`).
 
 ### Added
 
+- **Platformer: the LAVA SERPENT + a widened L4 lava pit (asset-expansion Phase
+  E).** L4's old collapsing bridge (which never read right) is **gone**; in its
+  place the lava pit is widened to a **512px chasm** (2944..3456, up from a 192px
+  strip) crossed in **two ~160px hops** over a middle **stepping-stone**, and a
+  rearing **LAVA SERPENT** (`snakeLava` art, bodiless) rises OUT of the lava, arcs
+  ACROSS it and sinks back in on a sine path, **peaking at the stepping-stone** so
+  it contests the very rock you must land on (time your hops between its rises).
+  New `pfMakeLavaSerpent` / `pfTickLavaSerpent`: a pure sprite created BEFORE the
+  lava tiles so the y576 tile row occludes its submerged lower body (it reads as
+  rising from / sinking into the lava), with a visibility toggle backing the
+  no-tile fallback; the head's strike zone is a proximity-poll knockback (the saw
+  rule, gotcha 16), never a stomp. The collapsing-bridge maker/tick/globals were
+  removed wholesale. Self-gates on `gSpooksOK` - absent the spooks sheet the pit is
+  simply a two-hop lava gap (always completable).
+- **Platformer: SNAKES - the slither movement type (asset-expansion Phase E).** A
+  new slime-family kind `snake` with its own tick: it crawls the floor and
+  AUTO-REVERSES at a pit edge or wall (a single floor-probe `b2kOverlap`
+  ahead-and-below the body per frame), so you place it without hand-tuning a patrol
+  band - `pMinX/pMaxX` are just the outer safety bound. Stompable on top / hurts on
+  a side touch like a slime (kind "snake" falls through to the classic verdict),
+  and the Phase-D defeat juice (dead pose, poof, fade, pop) carries it for free.
+  `pfMakeSnake pIdx,pX,pMinX,pMaxX,pTopY` is the LOW (`snake.png`) crawler; the
+  tall rearing `snakeLava`/`snakeSlime` art is the lava serpent above. Spook-sheet
+  `.png` art, so it self-gates on `gSpooksOK`. Deployed on L3 (turns at the spike
+  pit) and L4's lava-pit approach (turns at the entry pit and the lava lip).
+- **Platformer: spook slime/snake sprites sit ON the ground (alignment fix).** The
+  new spook-sheet skins (green/blue slime, snake) had inherited the FOES bind
+  offset (`pDY -6/-8`), which floated them ~9px: the foes art has soft, sparse
+  bottom rows that want a deep frame-sink, but the spook frames fill edge-to-edge
+  (zero transparent padding, measured against `enemies.png`), so feet-on-ground is
+  just `pFullH/2 - frameH*0.9/2`. Re-derived per frame (snake `pDY 3`, slimes `4`);
+  needs an OXT pass to confirm to the pixel (art alignment is statically
+  unverifiable). Example-side only; static gates clean, audit 0 findings.
+- **Platformer: defeat-animation juice (asset-expansion Phase D).** Pure polish,
+  no new mechanics, on the one shared slime-family defeat path (so it lifts every
+  level at once). A stomped foe now **fades out** over its ~700ms linger
+  (`blendLevel` 0 -> ~96) instead of blinking off, and the spook foes show a
+  proper **dead** pose rather than a hit-flash: the bat `bat_hit.png` ->
+  `bat_dead.png`, the mimic `grassBlock_hit.png` -> `grassBlock_dead.png`. The
+  slimes/snail/block-slime already played their `_flat`/`_shell`/`_rest` squash
+  poses, and the telegraphing foes already idle on rest frames (`barnacle_*_rest`,
+  `block_rest`, `bat_hang`). The fade window is short and only a stomped foe or
+  two ever fade at once.
+  - **A stomp DUST-POOF** (more juice): four little pale motes arc out of a
+    squashed foe (`pfMakeDustPool`/`pfDustBurst`/`pfTickDust`, the pooled-debris
+    pattern - eight bodies parked off-world, flung on the stomp, re-parked ~0.5s
+    later, so nothing is created mid-game). The motes are `b2kSpawnBall` bodies
+    (no new art) born in the camera group, so they scroll with the world. Built
+    every level.
+  Example-side only; static gates clean, audit 0 findings.
+  - **A defeat POP + second SKINS** (more juice): the squashed art now also POPS
+    up on an ease-out arc (~50px) as it fades; and the bestiary gains variants -
+    a **green** and **blue** slime (the `spooks` `.png` skins, via `pfMakeCritter`
+    which now takes an optional sheet; `gSpooksOK`-gated, a normal slime without
+    it) reskin two L1 slimes, and the **ring worm** (`worm_ring_*`, native foes)
+    reskins L2's worm. `tools/audit-platformer.py` learned that two same-index
+    makers are a conditional reskin (`if gSpooksOK ... else ...`), not two foes.
 - **Platformer: MULTI-KEY doors + a two-key puzzle in L2 (asset-expansion Phase C,
   slice 3 - part 1).** `pfMakeKeyDoor` was single-instance (one door per level via
   shared globals); it now appends to a per-door table, so a level can plant

docs/asset-expansion-plan.md

@@ -209,21 +209,47 @@ needs an OXT eye.
 - **Level:** a fortress interior — strong `block_strong_*` ?-blocks, a key/switch
   puzzle wing, spinner gauntlets, stone cliffs/overhangs.
 
-### Phase D — The defeat-animation & bestiary fill-in  (S–M)
+### Phase D — The defeat-animation & bestiary fill-in  (S–M)  — IN PROGRESS
 - **Assets:** `*_squashed/_hit/_dead` across `spooks` and `foes` `_rest` poses;
   `worm_ring_*` (second worm skin); `slimeBlue*`/`slimeGreen*` skins.
 - **Polish, every level:** play the proper **squash/dead** frame on a stomp (slimes,
   snail, snake, etc.) instead of just dropping the art; **rest/idle** poses for
   sleeping/telegraphing foes. Adds juice without new mechanics.
 - *Pure example-side; no new levels.* Good "between big phases" polish.
-
-### Phase E — Snakes & the slither biome beat  (M)
+- **Done (pending OXT):** the stomped foe now **fades out** over its linger
+  (`blendLevel` ramp) instead of blinking off; the bat + mimic show a proper
+  `_dead` pose (was a `_hit` flash); and a **dust-POOF** (four pooled `b2kSpawnBall`
+  motes, the debris pattern) bursts from the squash. Slimes/snail/block already
+  had `_flat`/`_shell`/`_rest` squash poses; telegraphing foes already idle on rest.
+- **Done (round 2):** a defeat **POP** (the squashed art arcs up ~50px as it
+  fades) and the **second skins** - a green + blue slime (`slimeGreen/Blue`,
+  `spooks`, via `pfMakeCritter`'s new optional sheet param, `gSpooksOK`-gated) and
+  the **ring worm** (`worm_ring`, native foes). Phase D essentially complete.
+
+### Phase E — Snakes & the slither biome beat  (M)  — BEGUN
 - **Assets:** `snake(.png)/_walk/_hit/_dead`, `snakeLava*`, `snakeSlime*`.
 - **New movement type:** **slither** — a ground crawler that hugs the floor and
-  reverses at edges/walls (slime-family kind `snake`, animated `_walk`). `snakeLava`
-  belongs by the L4 lava / Phase-B cavern; `snakeSlime` by slime pools.
-- Woven into L4 and the new biomes (no dedicated level needed, but could anchor a
-  "serpent pit" beat).
+  reverses at edges/walls (slime-family kind `snake`, animated `_walk`). The LOW
+  `snake.png` is the crawler; the TALL rearing `snakeLava`/`snakeSlime` art is the
+  rising **lava serpent** (a separate bodiless mover, not a floor crawler).
+- Woven into L4 and the new biomes (no dedicated level needed).
+- **Done (pending OXT):**
+  - The `snake` kind + slither tick (floor-probe edge/wall reversal) +
+    `pfMakeSnake pIdx,pX,pMinX,pMaxX,pTopY` — the plain low crawler, `gSpooksOK`-
+    gated, via `pfMakeCritter`'s sheet param. Deployed: L3's ice platform (turns at
+    the spike pit) and L4's lava-pit approach (turns at the entry pit + lava lip).
+  - **The "serpent pit" beat (`pfMakeLavaSerpent`/`pfTickLavaSerpent`):** L4's old
+    collapsing bridge is removed; the lava pit is widened to a 512px chasm crossed
+    in two hops over a middle stepping-stone, and a rearing `snakeLava` serpent
+    rises out / arcs across / sinks back in on a sine path, peaking at the stone
+    (a proximity-poll knockback, the saw rule). Created under the lava tiles so its
+    submerged body is occluded.
+  - **Sprite grounding fix:** the spook skins fill their frames edge-to-edge (no
+    transparent padding, measured), so their bind offset is the plain geometric
+    `pFullH/2 - frameH*0.9/2`, not the FOES soft-bottom sink that floated them ~9px.
+- **TODO:** a `snakeSlime` home (a slime-pool beat) and more snake placements;
+  optionally teach `audit-platformer.py` the `pfMakeSnake`/`pfMakeLavaSerpent`
+  makers (currently ignored — harmless, the pit isn't gap-checked).
 
 ### Phase F — Collectibles & a health model  (M)
 - **Assets:** `coin_bronze/silver(_side)`, `star`, `heart`, `hud_heart(_half/