XCOTA TAG V5.1 SPECIAL — 17 fighters, four controllers, RetroArch

V5.1 fixes source ZIP handling and prioritizes the supported Fightcade2
donor revisions. Four unused bytes after archived source tables become zero
padding, so all supported revisions build the same V5.1 Special game.
Gameplay, animation frames, character graphics and the four-player ABI stay
as released in V5. Use the matching core and V5.1 output from this package.

BUILD ON WINDOWS

1. Extract xcota-tag-v5.1-retroarch.zip into its own writable folder.
2. Select all FOUR complete clean game ZIPs together:

   X-Men: Children of the Atom — Euro 950331 (xmcota)
   Marvel vs. Capcom — Euro 980123 (mvsc)
   X-Men vs. Street Fighter — see SUPPORTED XMvsSF below
   Marvel vs. Capcom 2 — Naomi Export/Korea Rev A (mvsc2)

3. Drag all four onto BUILD V5.1 SPECIAL.cmd. Either order works.
4. The finished game is output/xmcotas4p.zip. Keep this name.

One outer ZIP containing all four individual game ZIPs also works. Keep
each game ZIP intact; don't mix their loose members into a single archive.
Flat members or one common folder inside a game ZIP are supported. The
builder explains missing games, unsupported revisions and invalid layouts.
Archive names do not identify revisions: actual source members and hashes do.

The normal XCOTA ZIP is xmcota.zip, with xmcota.key INSIDE it. A loose key
next to an incomplete ZIP is insufficient. All four inputs are preserved.
The XCOTA source remains Euro 950331. Older xmcotau, xmcotaj and xmcotar1d
revisions listed for V4.1 are not interchangeable with V5's Gambit recipe.
If a different output already exists, use a fresh builder folder.

SUPPORTED XMvsSF

Euro 961004 (xmvsf) is the preferred complete Fightcade2 donor. USA 961023
(xmvsfu) and Japan 961023 (xmvsfj) are also accepted. Split USA/Japan ZIPs
can read their shared members from a clean xmvsf.zip beside the clone. Keep
the parent ZIP beside it, or include both inside your outer game-ZIP container.
The exact accepted revisions and member identities are in source-inputs.json.
V5 incorrectly called Japan 961023 "xmvsfjr1" in its instructions. That name
means Japan 961004 in Fightcade2; use the actual revision above. A previously
renamed archive with authentic 961023 members still works. V5.1's regional
adapters read their real program files and regional key; they preserve each
consumed source field and the complete generated-game checksum. Do not rename
another revision's program files or key to make it look Japanese.

Windows inbox PowerShell 5.1 and .NET are sufficient. No Python, SDK, ROM
download or game key is bundled. BUILD V5 SPECIAL.cmd is a compatibility alias.

PLAY

Windows x64: run PLAY V5.1 SPECIAL.cmd and select your existing retroarch.exe
when asked. It verifies the game and uses the included matching Special core.

Apple silicon: use your existing arm64 RetroArch. Load the included
fbneo_xcota_special_expanded_libretro.dylib core, then output/xmcotas4p.zip.
The verified PowerShell host builder can generate the same game on this Mac.
Do not use stock RetroArch FBNeo, MAME or a renamed xmcota.zip for Special.

Assign separate controllers to ports 1–4 under Settings > Input > RetroPad
Binds > Port Controls > Device Index. Teams are 1+3 versus 2+4. HP+HK joins
from attract/selection. P1/P2 choose first fighters; P3/P4 choose partners.
Confirm with an attack. Start fresh; older-core save states are incompatible.

MP+HK tags. QCF+MP+HK uses a supported team super at full Level Max.
QCB+MP+HK starts paid timed Duo at full Level Max; X-Powers are free during
TIME. LK+MP in hitstun breaks for one bar; use only those two attack buttons.

Special retains Akuma and adds Gambit, Rogue, Sabretooth and Marrow. The
complete corresponding V5 Special core source remains included. Finite
XCOTA character adaptations and earlier game/controller evidence carry
forward; a new Windows game, physical-pad or online session is not claimed.
