Crossfire is a multi-player graphical arcade and adventure game made for the

Crossfire is a multi-player graphical arcade and adventure game made for the
X Windows systems environment. It has certain flavours from other games,
especially gauntlet and the rogue-like games (Nethack, Moria, Angband, and
Ragnarok.) Any number of players can move around in their own window, finding
and using items and battling monsters. They can choose to cooperate or compete
in the same world.

In the years of development that have followed, Crossfire has grown to
encompass over 150 monsters, ~3000 maps to explore, an elaborate magic system,
over 15 character types, a system of skills, and many, many artifacts and
treasures.