Open Tin Tower and Whirl Islands: Suicune, Ho-Oh and Lugia (#32)

Tin Tower's floors and roof and the Whirl Islands are open. The Clear Bell
gets the player past the sages to Suicune in Tin Tower; after the League,
the Rainbow Wing leads up to Ho-Oh, and the Silver Wing to Lugia.

New specials: MonCheck and BeastsCheck (CheckOwnMonAnywhere, with its
five-letter OT comparison and no Day-Care search).

The playthrough driver plans ledge jumps for the later stages, waterfall
descents, warp panels and Surf between warps; the run gains two stages,
Routes 45 and 46 back to Ecruteak and Tin Tower's Suicune.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/NATIVE_PORT.md

@@ -53,6 +53,7 @@ These paths refer to the pinned [PRET source](https://github.com/pret/pokecrysta
 | `game/scripts/cianwood.ts`, Routes 38–41, Olivine and Cianwood | `engine/events/shuckle.asm` (`GiveShuckle`, `ReturnShuckie`), `engine/pokemon/bills_pc_top.asm` (`CheckCurPartyMonFainted`), `engine/pokemon/caught_data.asm` (`SetGiftPartyMonCaughtData`), `engine/events/poke_seer.asm`, `engine/events/print_photo.asm`, `engine/printer/printer.asm` (`PrintPartymon`, `CheckPrinterStatus`), `engine/printer/printer_serial.asm`, `engine/events/specials.asm` (`PlaySlowCry`) | Shuckie is a level 15 party-only gift with MANIA's OT, ID 518, nickname, a Berry and `LANDMARK_GIFT` caught data; it sets `ENGINE_GOT_SHUCKIE_TODAY`. `ReturnShuckie` returns all five codes; `CheckCurPartyMonFainted` looks at the rest of the party, and Mania answers `SHUCKIE_FAINTED` with his happiness speech, as the original does. `PokeSeer` follows `ReadCaughtData`, including the missing `cp [hl]` that compares only the OT ID's high byte, `GetCaughtLocation`'s event and gift landmarks, `GetCaughtLevel`'s ??? that leaves `wSeerCaughtLevel` unchanged, and `SeerAdvice`'s inclusive thresholds. `wSeerCaughtLevel` lives in the "Miscellaneous WRAM 1" union: the port keeps the Seer's own last value until a load, while in the original other users of those bytes may change it. `PhotoStudio` has no printer to talk to: the handshake reads $ff, so `CheckPrinterStatus` reports `PRINTER_ERROR_2`, and `SendScreenToPrinter` retries until B sets `hPrinter`. The port shows "Printer Error 2" with "Press B to Cancel" on one page, then the no-photo text; the print page behind the box and its alternation with "CHECKING LINK" are not drawn. `PlaySlowCry` is audio. The story maps run on ported script commands; `tests/olivine-cianwood.test.ts` and six playthrough stages cover them. |
 | `game/scripts/lake-of-rage.ts`, Route 42 to Mahogany, the Lake of Rage, the Rocket Hideout and Pryce | `engine/events/magikarp.asm` (`CheckMagikarpLength`, `CalcMagikarpLength`, `PrintMagikarpLength`, `MagikarpHouseSign`), `engine/menus/intro_menu.asm` (`InitializeMagikarpHouse`), `engine/pokemon/search_party.asm` (`FindThatSpecies`), `engine/overworld/scripting.asm` (`DoScene`), `engine/events/money.asm` (`TakeMoney`) | The Magikarp is measured from its own DVs and OT ID with the battle code's `CalcMagikarpLength` (whose `.BCLessThanDE` compares only the high byte). A longer one, compared feet then inches, becomes the record with the Magikarp's OT name as holder; the record starts at 3′6″ by RALPH and is saved as `magikarpRecord`. `FindThatSpecies` reads `wPartySpecies`, where an Egg is EGG, so an Egg is never found. `setmapscene`/`setscene` on a map without a scene variable (Route 43, the Lake of Rage): `GetMapSceneID` leaves `de` alone and `DoScene` still writes the byte through it when it is nonzero. At the Route 43 gate `de` is `EventFlagAction`'s byte offset of `EVENT_CLEARED_ROCKET_HIDEOUT` (4), the MBC3 RAM-enable register, so nothing changes. After the Red Gyarados, `de` is whatever `closetext` left; the port consumes the byte and changes nothing, and that write was not checked in an emulator. `TakeMoney` leaves a short account at zero, so the Route 43 Rockets take all of a smaller balance. The Rocket Hideout's cameras, traps, passwords, executives and Electrodes and Pryce's ice floor run on ported primitives; `PlayCurMonCry` is audio. `tests/mahogany.test.ts` and five playthrough stages cover them. |
 | `game/scripts/blackthorn.ts`, the Radio Tower takeover, Ice Path, Blackthorn and Dragon's Den | `engine/events/dratini.asm` (`GiveDratini`), `engine/events/move_deleter.asm` (`MoveDeletion`), `engine/pokemon/mon_menu.asm` (`ChooseMoveToDelete`), `engine/events/whiteout.asm` (`Script_Whiteout`), `data/maps/setup_scripts.asm` (`MapSetupScript_Continue`) | `GiveDratini` searches the party backwards by species and writes `.Movesets` 0 (WRAP, THUNDER WAVE, TWISTER, EXTREMESPEED) or 1 with each move's base PP; a value of 2 or more changes nothing. `MoveDeletion` follows the routine's order of questions; `ChooseMoveToDelete` is shown as a list of the moves, and `.DeleteMove` shifts the later moves and PP bytes, PP Ups included. A save records objects whose visibility no longer matches their flags: `MapSetupScript_Continue` skips `LoadMapObjects`, so a flagless object a script made disappear (the Radio Tower director) stays gone after Continue and one that appeared with its flag set stays visible; a later visit rebuilds them from the map. A battle lost inside an `scall` jumps to `Script_Whiteout` without unwinding; its `newloadmap` is followed by `endall`, which drops the caller. The switch room's doors, the warehouse's reset, the Ice Path and Blackthorn Gym stone tables, whirlpools and the Dragon Shrine quiz run on ported primitives. `tests/blackthorn.test.ts`, `tests/radio-tower.test.ts` and six playthrough stages cover them. |
+| `game/scripts/tin-tower.ts`, Tin Tower and Whirl Islands | `engine/pokemon/search_owned.asm` (`BeastsCheck`, `MonCheck`, `CheckOwnMonAnywhere`, `CheckOwnMon`) | `CheckOwnMonAnywhere` returns nothing with an empty party, then reads the party structs' species (an Egg counts as its species), `sBox` and the fourteen `sBoxN` copies, matching the player's ID and the OT's first five letters (`NAME_LENGTH_JAPANESE - 2` compares, stopping early at a shared terminator); the Day-Care is not searched. The original's `sBox` is the current box, and its own `sBoxN` slot may still hold an older copy from before the last box change; the port keeps the boxes without stale copies, so a Pokémon only in such a copy is not found. The sages, Suicune, Ho-Oh and Lugia run on ported primitives (`BATTLETYPE_SUICUNE`, `BATTLETYPE_FORCEITEM`). `tests/tin-tower.test.ts` and two playthrough stages cover them. |
 | `game/scripts/slot-machine.ts`, `game/scripts/card-flip.ts` | `engine/games/slot_machine.asm`, `engine/games/card_flip.asm`, `engine/gfx/cgb_layouts.asm` | Both on a realtime tile screen (two frames per tick, buffered buttons). Slots: reel strips, spin rates and scrolling, bias tables with the lucky machine and seven streak, reel 3's Golem and Chansey replay with their sprites, payouts. Card Flip: deck, 12×11 board, cursor sprites and `ChooseCard_HandleJoypad`, paytable. Tilemaps, all 48 cursor positions, selected reel states and whole Golem/Chansey/Egg sequences are checked against the ROM (`tests/reference-game-corner.spec.ts`, which runs `CardFlip_UpdateCursorOAM`, `Slots_UpdateReelPositionAndOAM`/`.SpinReel` and the sprite-animation engine's own Golem/Chansey/Egg routines): the cursor, the reel symbols and the three creatures each anchor an OAM-relative pixel pair 8 (x) and 16 (y) beyond the screen's, as `cursorSprites` reads; `depixel`'s own two arguments end up swapped by `_InitSpriteAnimStruct` (confirmed against the reference emulator), so Golem/Chansey/Egg's X and Y bases were swapped to match, and Golem's own OAM table X-flips its right half. `PlaySpriteAnimations` is compared frame by frame over a three-Golem run and a Chansey round with two eggs (shadow OAM, `wSlotsDelay` and `hSCY`): frames last 8 ticks (the first draw plus 7 decrements); Golem's frames 3 and 4 flip the whole OAM set (offsets become −8−offset); a sprite removed by `DeinitializeSprite` is still drawn that tick, because `UpdateAnimFrame` runs after the animation function; the Golem's roll toggles `hSCY` by ±2, which the tile screen shows with the space tiles `_SlotMachine` filled the BG map with. The rows scrolled in use palette 0, since the attribute map beyond row 18 is not reproduced. No sound. |
 | Text interpreter                 | `macros/scripts/text.asm`, `constants/charmap.asm`, `home/text.asm`                                                            | Literal/far text, RAM names and string buffers from native state, numbers of dots, and sound or pause cues (consumed). `text_asm` and other RAM reads are refused.                                                                      |