This game is basically an action-remake of either Nethack or Eye Of The Beholder or both.
You ascend ino a crypt, battle devilish evil, and the game is over when you've come to the deepest level and finished the monster that lurks there.
Like in Nethack.
Only that in Nethack you are sent down to retrieve an amulet.
More on Nethack here :
http://en.wikipedia.org/wiki/NetHackNote : What Nethack lacks of graphical reperesentation it has gained in terms of ideas.