Co-op or Duke Match game?
For Co-op game you must place 7 sprites at the beginning of the level; they must have the texture number 1405 and a lo-tag of 1.
For Duke Match you must place 7 players with the same texture (1405), but without lo-tag, and at differents places, but without an advantage to a player from the others (near a good weapon, munitions...).
If you want that some objects to be in the game only in co-op or duke match, they must have the palette [Alt P] 1(blue).
Warning: for multiplayers games (serial, network, or sb-bot)
use simples levels with the version 1.3D because you can be desyncronised
than others players.
Remarque: you can put to each player a different color to differencied them.