/vr/ - Retro Games

Now this is a voodoo doll, Bloodfags

The VooDoo Doll glitch in Doom.

>place start position for player 1
>now place a second start position for player 1
>player 1 will start in the last placed start position
>in the others, an 'empty' player pawn will spawn
>he will do nothing at all, because he isn't controlled by any player
>but since both are player 1, anything that happens to the doll also happens to the player
>ergo if the doll is somehow injured or somehow picks up an item, the player does too
>if the doll somehow manages to pass over a walkover triggered linedef special, it will activate
Naturally, when this glitch was discovered, people started thinking of ways this could be exploited for the maps they're making. An obvious one is to make it a death trap for the player somehow, making a crusher kill the doll and thus the player, or perhaps a really tall crusher so that you have to beat the level before it reaches and crushes the doll, thus making it a timed mission.

In Final Doom, you can see it exploited somewhat, such as having the doll in a little box hidden from the rest of the level, and you can be made to telefrag yourself as a deathtrap, or the doll can sit on a ledge in a box and be lowered onto an item to give said item to the player.
People did this and that with the VooDoo Dolls, but where it really got off the hook is when Doom's source code was relaesed, and people made source ports such as Boom, which added features such as conveyor belt effects, which could be used wherever in your level, but then someone realized:
>Hey, what if I put a doll onto a conveyor like this, and put a bunch of walkover linedefs in a row in front of it, and the VooDoo doll gets released onto the conveyor because the player hit a switch or tripped an invisible walkover linedef himself?"
And people started doing just that.