Barnacle "Bill" Wilhelm is the second boss in Spear of Destiny and the boss of the Dungeon area.
Fighting Barnacle Wilhelm is very similar to fighting General Fettgesicht. The main difference is that Wilhelm is much faster than Fettgesicht and so it is imperative that the player keep their distance and pay attention to how much room they have to retreat. Wilhelm also has a slight hitpoint boost over Fettgesicht making him more durable.
Much like the fight with Fettgesicht in E6M9, the battle with Wilhelm in Map10 is lousy with enemies and blobby in shape, providing for many distractions and requiring that the player pays close attention to their surroundings.
Unlike Fettgesicht, defeating Barnacle Wilhelm does not trigger a game end event, but the gold key he drops leads to an immediate end of the map on Map10, so whatever ammo or health is left over after the battle will be carried over into Map11.
- Wilhelm is replaced in the Spear of Destiny Mission Packs by Professor Quarkblitz.