You were once probably thinking, "How do i make monsters warp into the map after a certain action has been activated/triggered." Well in this tutorial you will find out just how to do that!
Now it depends on what editor you use, for these instructions to make sense.. so i will try and talk more generally, so you have to be able to do basic mapping operations.
Well, open up a new map and create a room thats 512x512x256. Give the floor a texture of 'CITY1_4', the walls 'CHURCH1' and the ceiling a texture of 'CEILING1'. When that is completed, create a brush 64x64x8 near one side of the room and at the middle of that side
Now, select the top face of this new brush and apply the '+0BUTNN' texture to it. For the sides of the brush apply the 'CEILING5' texture. Turn this brush into a FUNC_BUTTON. Then give this button a 'target' of 'teleports', a 'sounds' of '3', a 'angle' of '2', a 'wait' of '-1' (button does not reset), a 'delay' of '2' and a 'message' of 'Look behind you!'. Now create a room of to the side of this room with the dimensions of 128x192x128. Don't worry about any textures in this room as the player won't enter this room. Place 2 enforcers in this room, one at each side (lengthwise).
Now create a brush that is 128x96x128, and use it to fill one half of the extra room, turn this brush into a 'TRIGGER_TELEPORT'. Give this entity these keys : 'targetname' = 'teleports', 'target' = 'tele1'.
Make a second brush the same as the one above but use it to fill in the second half of the room. Turn this brush into a 'TRIGGER_TELEPORT' and give it these keys : 'targetname' = 'teleports', 'target' = 'tele2'.
Now create a 'INFO_TELEPORT_DESTINATION' and place it in one of the corners, opposite to the button, of the main room, give this the keys of : 'targetname' = 'tele1'.
Create another in the other corner (away from the button) and give it this key : 'targetname' = 'tele2'.
All you have to do now is place a 'INFO_PLAYER_START' somewhere in the main room and compile! Voila! When you press the button, in comes 2 enforcers for you to slaughter
