From the back of the adventure:
"Buffalo Castle is the first adventure written specifically for solitaire play, designed for use with Tunnels & Trolls warrior characters. It is an excellent introduction to FRP game playing and solitaire adventure play in particular. Buffalo Castle has an abundance of rooms, traps, monsters... and treasure!
Buffalo Castle is Number 1 in a series of unique Solo Dungeon Adventures designed for play with the Tunnels & Trolls system of fantasy role-playing. If you have difficulty gathering enough friends to play T&T together, or if you have only a little time to play, then the Solo Dungeons are designed for you. You need only the rules for Tunnels & Trolls, a few six-sided dice, paper, pencil and this booklet to play."