Zombie Researchers are enemies from Metroid Fusion.
Zombie Researchers are deceased human scientists who were killed in a breakout of parasites known as the X. The X possessed them and transformed them into semi-humanoid, slithering blobs of purple goo wearing dirty, torn lab coats. Suiting to their nature, when the X killed and zombified them, they took their knowledge and used it to take over the space station.
The only way they damage Samus is by collision, but they can get a short burst of speed and do this deliberately. A single strike from any weapon will reduce them to a puddle of sludge; however, this sludge cannot be destroyed, so any X can raise it back to zombie state.