XEEN: Swords map UnderWorld broken

[HendrikR]

The endgame of "swords of xeen" has several bugs which keep a player from completing the game. The player has to visit the UnderWorld map to get the Negative Orb, necessary to win the game.

ScummVM Version: tested with both 2.6.1 and a fresh build from 2023-01-09 (commit id 611efe9b9088bc51a61679c39289a7f81f83df06).
Game Version: swrd.cc: 0d51c3457070cc7d1a596da9241924a5, 13026924 bytes.
Host OS: (Arch)Linux x86_64

1. When jumping from "Sky Platform" (maze0052) at pos (7,8), you are supposed to land in the UnderWorld (maze0078). Instead, you always land in map E6 (maze0038). The UnderWorld can only be reached by using "map 78" in the debugger.

2. The UnderWorld map (maze0078) itself has a bug that keeps it from loading. Upon reaching it (via "map 78"), scummvm crashes, because it cannot find 000.mon and 000.att files. In fact, these monster files do not exist. Adding them in the data directory (where sword.cc resides) makes the level accessible, but it then crashes as soon as one approaches the 3rd form of the GateMaster.

The broken GateMaster seems to be due to a missing entry in the monsters.swd file, as extracted from the swrd.cc archive. This file determines which sprites to load for which monster, and it only contains 2 of the 3 forms of the GateMaster (who occurs in 3 consecutive forms in the UnderWorld), the "egremlink" and the "dwolf" forms. The final form (a fire demon) is missing. As it is at the very end of the file, it might be due to a wrong filesize marker in the swrd.cc archive, or the file was simply truncated during creation of the archive.

[dreammaster]

Thanks for the comprehensive info. I'll try to look into it in the next few days.

[dreammaster]

Okay, I tracked down the custom changes Swords did for clouds falling logic, and it's now properly implemented. Just need to look into the map 78 crash now.

[dreammaster]

And the Underworld crash is now fixed as well.