Nothing beats the little flash of a loot beam cutting through the dim corridors of the Stronghold Slayer Dungeon — that’s where the rare stuff shows itself. In 'Old School RuneScape' rare drops in that dungeon appear exactly where the monster dies: on the tile beneath the corpse. Practically speaking, that means you need to pay attention to every corner,
Choke point, and stair landing where monsters are getting smacked down. A lot of players focus on the obvious combat rooms, but I’ve picked up uniques tucked behind a boulder or at the base of a staircase simply because I wasn’t tunnel-visioning on the main spawn.
Mechanically, rare drops are governed by drop tables (including the special rare drop table), and the game will mark particularly rare or unique items with the loot beam and chat message — so listen for the sound and watch for light. If you’re on a slayer task, most slayer monsters in the Stronghold are assigned to you, which kills most of the competition for drops. Otherwise, whoever deals most damage or tags the monster often gets priority pickup for a short time, so be mindful when you’re sharing the cave with others.
Practical tips: clear the room before loot checks, use safespots so you can tab in and out, and keep teleport gear handy so you can bank without wasting time. I still love that rush when a beam shows up; it never gets old.