Spear of Destiny is a prequel to Wolfenstein 3-D. It is a first-person shooter that uses the same engine and has the same gameplay, however, the game is not divided into 6 separate episodes - all the levels are one long episode. The enemies and weapons are pretty much the same as in Wolfenstein 3-D. Only new additions include new bosses, a new type of enemy, and a new pickup (a large box of ammo). (mobygames.com)