Frenzy followed the basic paradigm set by Berzerk: the player must navigate a maze full of hostile robots. The goal of the game is to survive as long as possible and score points by killing robots and travelling from room to room. The game has no end other than the player losing all of his or her lives.
The player has a gun with which to shoot the robots, and simple intelligence of the robots means that they can often be tricked into shooting one another. If the player lingers too long in a room, a bouncing smiley face (known as "Evil Otto") appears, and relentlessly chases the player. Evil Otto will destroy any robots in his way, and can move through walls.