Another thing about Wonder Boy in Monster Land: just about every foe has a death animation. Most side-scrollers of the NES and Sega Master System didn’t bother with this. Enemies exploded, flickered, or flipped off of the screen upon dying. Wonder Boy in Monster Land, on the other hand, gives each defeated creature a single-frame demise.
The most striking one comes from the mushrooms that amble toward Wonder Boy in the early stages of the game. At first, they look sedate and dutiful.
Then Wonder Boy stabs one, and its face changes to a look of pure agony. The creature’s final half-second on Earth is spent in tearful horror, gazing not toward Wonder Boy but out at the player. Or perhaps it’s looking at the vast spectrum of all it'll never be, at everything it longed to do with its brief fungal existence. A glimpse of a life unfulfilled torments this mushroom soldier, who couldn't even be a Goomba in Super Mario Bros., just before it vanishes from the world, leaving behind nothing but regret. And a shiny coin for Wonder Boy.
Many enemies in the game have their own death throes, but nothing so memorable as the mushroom underling. And Wonder Boy? He doesn’t react at all. As I pointed out years ago, Wonder Boy is a bit creepy.