You must have 7 Slayer to kill this monster.
Kill this fast as it heals quickly, this shouldn't be a problem as it is a very low creature. Killing Cave bugs are a very good strategy to defence pures. Since defence pures have 1 Attack and Strength, they can only hit 1-2s, and that's how much Cave bugs can heal by.
A nasty crawling critter.
Coins (2-8), Water rune (1-8), Nature rune (1-8), Earth rune (6), Eye of newt, Unicorn horn dust, Limpwurt root, Red spider eggs, Candle, Snape grass, Candle lantern, Grimy herbs, Tinderbox, Whiteberry, Water battlestaff, Red spider's eggs, Swamp weed