The Queen Plaga is a boss fought in the Tower summit at the end of "Chapter 4-4". It has two body sections with their own hitpoints - the tentacles are worth 200 and respawn, while the body (with Salazar in it) is worth 3000. The body has to be completely depleted in order to defeat the boss. On the bottom floor, there are up to three Plaga Cs walking about. If any are killed, more spawn to replace them indefinitely until the end of the fight.