Starting from the central square, Use arrow keys to move around gaining prizes (yellow). Entering a square needs either the right weapon to defeat the monster (reddish) there, or as many seconds as the strength of the monster (A-Z = 1-26), and scores the prize in score units. Aim for highest score when time runs out.
Other keys: Z to zero high score, P to pause or unpause.
Spells: T to teleport randomly, L to lightning bolt (eliminate) any monster in a random adjacent square, S to scramble/shrink all adjacent monsters into weaker sorts. (Magic is unreliable, but powerful.)