Dagannoth Rex Best in Slot Gear & Strategy Guide

Rex lives on the sixth (deepest) floor of the Waterbirth Island Dungeon, in the shared Dagannoth Kings' lair, reached via the Kings' ladder. There are two versions of the lair: a normal one, and a separate Slayer lair you enter by using the "Slayer" option on the ladder when you are on a Dagannoth task. You can peek through a crack in a safe room near the ladder to check whether the arena is already occupied before you drop in.

Three Kings share the island and each uses a different attack style, so you must match a different protection prayer to each: Prime uses magic and is weak to ranged; Rex uses melee and is weak to magic; Supreme uses ranged and is weak to melee. Rex spawns and roams on the south-eastern side of the lair. The key danger when hunting Rex is wandering too far west and waking Prime, who hits the hardest of the three and can hit up to 50 with his area-of-effect magic attack — keep your Protect from Magic ready and stay south-east.

Rex can be assigned as a Dagannoth Slayer task by Vannaka, Chaeldar, Konar, Nieve or Duradel, in which case you can wear a Slayer helmet (i) on task and use the dedicated Slayer lair (entered with the "Slayer" option on the Kings' ladder). The wiki's suggested skills for the Kings are around 70+ Attack, 70+ Strength, 75+ Magic, 70+ Ranged, 60+ Defence (80+ recommended), 70+ Hitpoints, and 45+ Prayer for Mystic Might (70+ for Piety). If you are only here for Rex, the magic level matters most — with a decent Magic level you can wear full melee armour for its defence and still hit him consistently. An 85 Agility shortcut (or 80 with a Summer pie boost) skips the long tunnel route and removes the need to carry a rune throwing axe and pet rock.

Because Rex has extremely low Magic Defence, the meta is to attack with magic while wearing high-Defence melee armour — you get strong damage reduction yet still hit him reliably even with a negative magic attack bonus. Barrows armour is the classic choice; Guthan's equipment is popular because its set effect lets you heal off the Spinolyps between kills. Lean toward gear with high Ranged Defence and a prayer bonus, since the Spinolyps in the surrounding moat attack with ranged-based magic and are the main drain on your supplies. For your spell, the wiki names Slayer Dart, Iban Blast, powered staves and Earth spells as popular options; as of 25 June 2025 Rex also has a 35% elemental weakness to earth spells. Rather than chase an exact item list, build your loadout with our Boss Gear Finder.

Supplies to bring:

• Antipoison protection (Antidote++ or Sanfew serums) — the Spinolyps poison, starting at 6 damage. Not needed if you wear a Serpentine helm.
• 4–8 Prayer potions (or super restores), plus emergency food (sharks, or Saradomin brews / super restores).
• A rune pouch with runes for your spell — Blood spells let you heal off Rex and the Spinolyps; Ice spells can freeze Rex.
• A herb sack for grimy ranarr weed, and an emergency teleport.
• Rune thrownaxe and pet rock to make the trip (skippable with the Agility shortcut).

Melee attack (Slash, max 26). Rex's only attack is melee on a 4-tick speed, so the answer is simple: pray Protect from Melee. With high Defence bonuses he is fairly inaccurate against you anyway.

Safespotting. Because Rex is large and only attacks in melee range, you can lure him onto a ridge where he gets stuck and cannot reach you. From the eastern wall, attack him with a long-range spell or staff; as he approaches, pray Protect from Melee and move north or south until he is wedged against a wall, then keep casting freely from safety. Safespots exist on the north-eastern, south-eastern and north-western walls.

Spinolyps. These creatures inhabit the moat around the island and keep attacking even while you safespot. They have 75 Hitpoints, are not very accurate (especially against high ranged-defence armour), and their ranged attacks inflict poison while their magic attacks drain a prayer point on hit. They are also a feature, not just a nuisance: with Guthan's, a Saradomin godsword, blood spells, a Regen bracelet, a Hitpoints cape or a Sanguinesti staff you can passively heal off them between Rex respawns to greatly extend your trip.

If you only want Rex, the routine is short. On entry, activate Protect from Magic before dropping in, since Prime is accurate and hits hardest. Then enter and exit the room (leaving via the ladder cancels some incoming attacks if done quickly) until you can run along the southern side of the island unnoticed by Supreme or Prime. Once on the eastern wall, hit Rex with a long-range spell, pray Protect from Melee as he closes in, and shuffle north or south to wedge him on a wall. Cast away, top up off the Spinolyps as needed, and collect his drops between respawns. Stay cautious even in the safe area — other players have been known to drag Prime's AoE attack onto you.

Every kill drops Dagannoth bones and a Dagannoth hide (the bones drop noted if you have completed the elite Fremennik Diary, which substantially boosts trip profit). His marquee uniques are the Berserker ring and Warrior ring — Rex is the only monster that drops either — plus the rare dragon axe, each at 1/128. He also has a 1/5000 chance at the Pet dagannoth rex. Lower-value but frequent drops include a Mithril warhammer and noted Mithril ore. The full drop table with rates is shown above; check live prices any time with our GE Price Tracker.

• Fighting Rex with melee. He resists melee but folds to magic — bring a spell, not a whip.
• Wandering too far west to lure him. That wakes Prime (and possibly Supreme); Prime drifts east/north-east and is the bigger threat. Stay south-east and only pull Rex when he is nearest the east.
• Forgetting antipoison. The Spinolyps poison from 6 damage upward; without protection (or a Serpentine helm) the chip damage drains your food fast.
• Entering without Protect from Magic up. Prime is very accurate and hits the hardest of the three, so the prayer should already be on before you drop in.
• Not healing off the Spinolyps. Guthan's, an SGS, blood spells or a Sanguinesti staff turn the moat creatures into free healing and massively extend trips.