playing a bit with the two linedefs that monsters can trigger in Doom by moving over them. I feel they could be used for something similar to voodoo doll logic. instead of pushing players around, monsters start moving by virtue of either being spotted by the player or by the player shooting. monster movement is pseudorandom, so they behave similar to a gas
>data input
the player opens/closes doors using buttons
>AND
two or more doors in series
>OR
two or more doors in parallel
>clocks
have a monster circulate by way of a series of lifts terminated by a teleporter that brings them back
>NOT
haven't figured out how to do this, but it must somehow involve monster presence in one area inhibiting monsters passing through some other area. maybe a large monster like a Caco can be teleported into an area from which they can't leave, thereby preventing the passage of a smaller monster like a Lost Soul?
>display
monsters are teleported into a lil' jail cell that the player can see