Xarpus is the fifth encounter in the Theatre of Blood. The Yarasa King, Xarpus is the last of its kind, and was captured by Lord Lowerniel Vergidiyad Drakan to be used as a boss in the Theatre. Despite his connection to bats, Xarpus does not count for a Bat Slayer task.
Xarpus has three phases:
A group of players fighting Xarpus.
- Recovery (Phase 1): Severely weakened, Xarpus will channel the energy of the ground by exhuming a total of 25 skeletons to heal him for rapid bits of 6 health per tick for 15 ticks. This can be temporarily halted by standing on top of the exhumed remains.
- Poison (Phase 2): Xarpus starts attacking the players after enough time has passed from phase 1 and starts off with the amount of health he had starting from phase 1. He will launch poison at players which lightly damages anyone in a 3x3 grid centred around the player Xarpus was focusing. This poison then occupies that tile for the rest of the fight and deals 6-8 damage each tick a player stands on or crosses over it. Skipping over a poisoned tile will deal a delayed hit.
- Counter (Phase 3): Xarpus screeches once lowered below 25% of its health and stops launching poison around the arena, instead staring intently at one quadrant at a time. If a player attacks it from the area Xarpus is looking at, he will retaliate with a poison attack. 
- ^ Only received if players do not have it stored in their bank.
|3 June 2021
(update | poll)
- Hard mode and entry mode versions of the Theatre of Blood encounters added.
- The word "Yarasa" in its examine text was changed to "yarasa."
|16 May 2019
The difficulty of phase 1 was reduced, especially for solo-trio teams.
- "Yarasa", the species that Xarpus is classified as, means "bat" in Turkish.
- When examined, the acidic miasma that Xarpus shoots at the players reads "Tread softly because you tread on miasma". This is a reference to the poem Aedh Wishes for the Cloths of Heaven by W. B. Yeats.