Monkey tails are a component in making heavy or light ballistae. It is dropped by demonic gorillas in the Crash Site Cavern, and can also be received as a very rare drop (1 in 5,000) from hunting maniacal monkeys with a deadfall trap in Kruk's Dungeon.
Monkey tails can be attached to an unstrung light or heavy ballista to create a light or heavy ballista, respectively. Attaching a light one requires level 47 in fletching, granting 300 experience in doing so. Attaching a heavy one requires level 72 in fletching, granting 600 experience in doing so.
Dropping monsters[]
Monster Combat level Quantity Rarity Demonic gorilla 275 1 Very rare (1/1,500) Maniacal monkey (Hunter) N/A 1 Very rare (1/5,000) Tortured gorilla 142 1 Very rare (1/15,000)