You open the Locked Door, and find yourself staring at the level's boss face to face. However, instead of the battle immediately commencing, he taunts you, begins to run away, and exclaims that if you want to fight him, you'll have to catch him first. As you chase him throughout the subsequent Death Course, evading enemies and negotiating obstacles, you notice that the boss is in plain sight. You whip out your Weapon of Choice and unload on him, but he doesn't die. In fact, he appears to take no damage whatsoever. You find that it's not until you reach the Boss Room and the Boss Battle officially begins can you successfully deal damage.