Cyberdreams

Cyberdreams is a 1998 megawad by Gonzalo Pèrez de la Ossa and Albert Valls. It is well known for featuring puzzles involving Cyberdemons in each level, which the player is forced to solve without the use of weapons.

Overview
In all levels the pistol and fist are the only available weapons, and nearly all levels require the player to kill the Cyberdemons. Often this is by using clever techniques such as telefragging, activating crushers, making the floor below the Cyberdemon rise so that the height of the room it is in is not high enough to contain it and eventually kill it, and starting monster infighting between it and other monsters. Most levels require the player to activate switches while under fire from the Cyberdemon's rockets (sometimes ridiculously heavy fire), or to dodge rockets while waiting for a crusher destroy the Cyberdemons.

Levels
'''SPOILER WARNING: Don't read this if you intend to figure out how to beat the game yourself. '''

Warm Up: One on One --  As the level name makes clear, this level is you versus one Cyberdemon. To win, you must lure the Cyberdemon to the center platform, then move through one of the four teleporters at the corners of the room to telefrag him. You must do this in order to beat the level, because pushing the switch to attemt to reveal the exit will trap you, free for the Cyberdemon to kill.

The S-2 Factor --  In this level, you must navigate barriers in order to get to telporters to telefrag two Cyberdemons, all the while dodging their fire.

A Bridge Between --  To win, you need to activate four switches. You must go back and forth across a bridge that is flanked by two Cyberdemons, which will continuously fire at you, hitting the switches that will raise the floor sections to activate the sectors that will kill the Cybers. The bridge in the middle has a wallrunning capable sidedef that can be exploited. After going through the platform behind the Cybers, they will eventually be killed, and the exit revealed.