There are some things that most people don't know about walls. Walls are more complex than they look.
Walls tagged [1,0]
A wall with a Hi-Tag of 1 is excluded from a certain function or effect. This is most commonly used to stop a wall from changing it's shade value when the rest of the sector's shade changes. So if a sector lights up, any wall with a Hi-Tag of 1 in that sector will not be affected by the light.
Walls tagged [0,Channel]
Any wall with a DOORTILE texture and a Lo-Tag can trigger an effect when activated using the action button (default Spacebar
). Give the wall with the DOORTILE texture and an Activator (or ActivatorLocked/Masterswitch) the same unique Channel. When the player presses against the wall, the Activator (or ActivatorLocked/Masterswitch) will activate.
DOORTILE textures (A DOORTILE texture is any texture with the name DOORTILE appended to it) : #150 to #159, #395, #447 to #449, #717, #781, #1102, #1144, #1169, #1178, #1179, #4391.
Walls tagged [0,SoundToPlay]
Any wall with the MIRROR texture can play a sound when the mirror is pressed against. Just give SoundToPlay the number of the sound you want to play.