Dungeons of Kathallion is a text adventure game about the player venturing into mysterious dungeons after their kidnapped friend.

It begins with this dialog:

Once upon a time, you and your friend, Jake, were playing by an ancient castle. Or rather, there was the Great Wizard Jaketroth and his companion, the Knight of Valor. There was great worry in the land of a monster that comes out of the great ruins of the Castle of Kathallion. But it was vanquished by the might of the two heroes. 'That was fun!' Jake laughed as he stuck the boulder with is staff. 'I wish we could go on a real adventure, though.' Then a tentacle shot out of a hole in the ground, and pulled Jake down into it. 'Help!' he cried. You leaped up and ran to the opening. You could see nothing but a trail of slime. Quickly, you looked around for something. There was an old set of armor and a sword inside a fallen tower. You took them and run back to the hole. On your way, you trip over something. It is a potion, labeled 'To Heal the User back to Full Strength and Might'! You pocket it and leap down.