You already know the room. The creature is the constant. You are the variable.
The shore task. Kings on Bosses.
Slayer · RuneScape
Where
Waterbirth, Lighthouse
Assigned by RuneScape slayer masters. The live page lists who.
Hunt
The shore task. Kings stay on Bosses.
Watch
Task-only doors, face covers, and cannon-blocks are on the live page. Confirm on the wiki.
Kill
A kill ends when dagannoth drops. Walk the room if you pulled extras. Reset at the door when the task is done. Wrong prayer or the wrong tile is the wipe. That is the whole file. Do not treat this as an enrage boss. Those sheets live under Bosses. Counts, drops, and the living method: the RuneScape wiki for this hour.