Here shall be discussed how the multiplayer modes shall be designed and integrated into the game.
For easy overview without tons of explanation, I have created a dia where the first basic ideas are shown. Please download the .dia file to modify and re-upload also as .png to allow a quick look.
Players play their own game (after death immediate respawn at start), but can see each other in the level: -not much Multiplayer Effect, but fun. Fun because you try finishing a hard level first. With lots of deaths it can be fun, because its still competing.
Players start simultaneously, after death, the player has to wait for the other to die or finish the level.
Special Levels which need cooperative Help to be finished (heavy scripting there).