Doom for VAX VMS is a multiuser text-mode game, written in autumn 1997 by Oleg Sobolev.
Player can move only in one of four direction, and the position is limited to map cells. To run the game in multiplayer mode, set CM_NOMON variable:
$def cm_nomon
Equ value: 1

A screenshot of ASCII DOOM

Download doom (zip file with sources, sprites and makefile : 22K )