Hello Nicolas.

> This should be gnu/packages/games.scm (bsd-games): New variable.

> reference all those patches in "gnu/local.mk" file.

Done

> some games still fail to run, e.g., phantasia and hack.

Pity.  What errors are output?

How i do start the games:

cd git/guix
guix environment --pure guix
./bootstrap && ./configure --localstatedir=/var && make -j2
./pre-inst-env guix environment --ad-hoc bsd-games
phantasia
--->
   Guix: Please set up the BSD_GAMES_DIR variable.
   Examples:
      export BSD_GAMES_DIR=/var/multiplayer
      export BSD_GAMES_DIR=~/.local/share/bsd-games
   You can place this in ~/.bashrc or a similar file for Your shell.
   For multiplayer this directory should be writable for all players.

BSD_GAMES_DIR=~/bsd-dir phantasia
--->
   "You've been caught raping and pillaging"
   "You are attacked by Kobold"
   ...
---

Regards, Vitaliy.
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