End mob in the "Ring of Slime" event in the Slime pools in Cazic Thule. Slime pool is accessed from down the well to the south near the zone-in. One of the swirling oozes in the green pool is perma-rooted and a raid con.
a swirling ooze (Lvl: 56) -> a bubbling ooze (Lvl: 60) -> a boiling ooze (Lvl: 63) -> an acidic mass (Lvl: 64) which spawns an acidic ooze (Lvl: 56) as adds during the fight.