Carla Radames (Resident Evil 6)

Carla mutates into a grotesque J'avo version that is practically invincible. When you first meet Carla, you have only one choice - escape. She spreads herself throughout the ship like an uncontrollable blob, blocking off corridors and spawning appendages to stop you escaping. She even has the ability to spawn copies of former self that will casually chase you down unless you destroy them before they catch you.