The Lost Vikings/YMMV


 * Awesome Music: Lost Vikings 1 and Lost Vikings 2 both have awesome, if somewhat limited, soundtracks. Norse By Norsewest has much more variety, but whether it's any better is very much a matter of preference.
 * Demonic Spiders:
 * Cavemen and egyptians in the first game; wizards and gorillas in the second game. Cavemen and gorillas ball up and roll around making themselves invincible. Egyptians jumps around, easily bypassing Olaf's shield. Wizards constantly disappear, only rematerializing long enough for you to whack them, or, more likely, for them to nail you with a magic blast.
 * The rolling blades in the Factory World of the first game. They're the only enemy that can hurt Olaf through his shield.
 * That One Level: Rivets in the Genesis version of The Lost Vikings.