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By extension, the entire Super Metroid Manga. Seriously, if you haven't read it, go read it. You can find it on the Metroid Database.
Super Metroid's Crocomire, who suffers a Family-Unfriendly Death by being forced onto a none-too sturdy bridge over a pool of acid, then falling into the acid, which melts his flesh off, leaving nothing but his skeleton. And then, the skeleton breaks through the spiked wall behind Samus to get his revenge against her... only to crumble to dust, leaving behind his skull.
In Super Metroid, crashing into the ceiling with the Shinespark move will embed Samus's head into it with an audible thud, complete with afterimages of Samus as Circling Birdies and double vision.
Mini-Kraid. Just the idea of Mini-Kraid alone.
The Yard from Super Metroid is an enemy found in Maridia that looks like a giant snail. Shooting it causes it to retract into its shell, which can then be knocked around. It actually bounces when hit, so Samus could play a game of kickball with a startled Yard.