Slayer masters assign you a task to kill a set number of a specific monster. Each master lives at a world place — Torvak in Lumbright, Morven in Canifel, Valdrin in Edgevale, Caelira in Seerhold, Nyra in Camlann and Druven in Brimhollow — and getting a task is an action at that settlement: visit the master (the Slayer screen or the world map offers to travel there if you're elsewhere) to be assigned. Completing tasks earns slayer points and Slayer XP; higher-tier masters need higher combat and Slayer levels and pay more points. Killing your assigned monster is the only way to finish a task, and it counts wherever you kill it — idle, live, in the open world, or fighting a boss or raid with a group — you can also spend credits to skip a task, or slayer points to buy unlocks (found on the Character Unlocks screen) and rewards. Boss slayer tasks award a ×4 Slayer XP multiplier on kills. The Auto Slayer Task unlock (100 credits, on the Character Unlocks screen) keeps your slayer grind going while you're away: when you're idling on your assigned monster, finishing a task automatically takes the next one from the same master, so offline catch-up and Skip 1h can complete several tasks in a row instead of grinding the finished monster. A boss task can't be auto-fought, so the chain stops there and leaves it assigned for you. Every slayer monster also drops farming seeds and saplings, tiered by its Slayer requirement: low-level tasks drop basic herb seeds and oak saplings, while the toughest monsters and slayer bosses rarely drop rynarr seeds and yew, palm and magic saplings.
Two extremely rare materials — the Imbued Crown and the Imbued Brain — can drop from any slayer-level-gated monster or boss, but only while that monster is your currently assigned slayer task; killing the same monster off-task never rolls them. Odds scale with the monster's Slayer requirement, from 1/25,000 (Imbued Crown) and 1/150,000 (Imbued Brain) at the lowest requirement up to 1/250 and 1/1,500 at the highest (Ashen Hydra). The Imbued Crown combines with a Slayer Helmet to forge the Imbued Slayer Crown, which extends the helmet's melee bonuses to ranged and magic as well. The Imbued Brain is an unlimited-use item — drinking it grants +18 Magic for 5 minutes without ever being consumed.