Viper

Viper is a 1-player arcade game for the Apple II.

The player controls a snake that can move in the 4 cardinal direction. On the screen appears a mouse, who will slowly move about. The goal is to move the snake so that it eats the mouse. Every time the snake eats a mouse, it elongates, and a new mouse appears on the screen. If the snake runs into a wall or its own tail, the player loses a life. The player gains 3 points for every mouse eaten, and gains a new life at 500 points. The player can define mouse and snake speed, as well as how many obstacles appear in the play field. The player starts with 3 lives, and when all are lost, it's game over.