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Osseous Basic


Osseous, the skeletal Rex Matriarch, can be fought after completing the Osseous Rex quest, which requires 70 Necromancy necromancy and 30 Archaeology archaeology. Her unique drops consist of the Occultist Ring occulistring and the Jail Cell Key, which can be used to unlock three separate dinosaur pets. Similar to the other Rex Matriarchs, she drops the Heart of the Berserker berserkerheart and parts of the Laniakea Spear speartip spearcap spearshaft spearplume.

The fight itself is one phase. The aim of this guide is to familiarise you with how to handle mechanics in order to successfully get your first solo kills.

Throughout this fight, the player will pray Deflect Necromancy deflectnecromancy or Protect from Necromancy protectfromnecro. If the player has access to Soul Split soulsplit then use this instead.


Attack Rotation
2 necromancy Auto Attacks → range Auto Attack → necromancy Auto Attack → Minion Summon → necromancy Auto Attack → range Auto Attack → necromancy Auto Attack → Minion Launch → 2 necromancy Auto Attacks → Osseous Roar → 2 necromancy Auto Attacks → Munch → 1 necromancy Auto Attack → Repeat
Minion Summon
⬥ Osseous will turn around and slam her tail into the ground. This slam will deal heavy melee melee damage as well as summon six baby dinosaur skeletons. Any baby dinosaur skeleton that reaches Osseous will heal her for 5-10% of their current life points. The player should: • Use Resonance res to heal from the melee hit.     • If Resonance is on cooldown, Protect from Melee protectfrommelee or Deflect Melee deflectmelee and use Devotion devo for 100% damage reduction. Then switch your prayer back to Deflect Necromancy deflectnecromancy or Protect from Necromancy protectfromnecro. or     • Use Reflect reflect to reduce the damage by 50%.     • Ignore the baby dinosaur skeletons for the time being. • Click to view an example of Minion Summon
Minion Launch
⬥ Osseous will quickly spin around and launch one of her minions at each player in the arena and stun the player for 3 seconds. Any extra baby dinosaurs will seek out players and attack them using melee melee. The player should handle the baby dinosaurs by: • Making sure your target is still Osseous.     • Using Command Putrid Zombie commandzombie (no adrenaline cost). or     • Casting Spectral Scythe three times spectralscythe spectralscythe2 spectralscythe3 (60% adrenaline cost). The stun lasts for 3 seconds and the baby dinosaurs take 3 seconds to rush the player. Therefore, the best time to use the abilities above is when the stun expires. If the baby dinosaurs are not killed, they will explode when Osseous' Roar occurs and deal damage to the player. Kill any remaining.Click to view an example of Minion Launch
Osseous' Roar
⬥ Osseous' roar pulls the player to melee distance of her and binds them in place. Any minions left alive will explode, dealing 50% of their current life points to nearby players. • Click to view an example of Osseous Roar
⬥ Osseous roars, pulling the player to melee distance of her and binding them in place similarly to the above mechanic. Osseous will bind the player until they have dealt 5k damage to her. An adrenaline bar will appear over Osseous' head when she uses this, and as the bar is completely filled she will bite the player for ~6000 typeless damage. The player should: • Use res to nullify the damage from the bite. • Click to view an example of Munch

Presets and Relics

Below is a preset we believe will lead to a great learning experience.

Necromancy is the only possible style that can damage Osseous. The preset below is not set in stone so if you are missing a couple of items, you will still be able to complete kills. Try not to downgrade too heavily though as these have been prepared with your learning experience in mind.

Preset Suggestions

Tips and Tricks

Osseous will teach you how to mitigate damage from big hits using Defensive abilities effectively. You will also learn how to handle Area-of-Effect (AoE) mechanics and the basics of a good rotation for damage output.

Primarily in this fight, you will use Resonance res and in some cases, you may use Devotion devo or Reflect reflect to reduce incoming damage. If you have Lesser Bone Shield lesserboneshield unlocked and active, you do not need to bring a shield with you to access Resonance res or Reflect reflect otherwise you will need to bring a shield. Keep in mind that equipping shields will despawn your conjures unless it is a Spectral spirit shield spectralspiritshield or a Dragonfire Shroud.

Once you are comfortable surviving and getting kills successfully at Osseous, it's time to practice some fundamentals for Necromancy ability rotations to increase your damage output. Below is a basic structure to think about and practice to try:

1) Damage boosting ultimate ability ‎ ‎- Living Death livingdeath

2) Build adrenaline, souls or necrosis stacks using appropriate basic abilities

3) Stronger threshold abilities e.g. Finger of Death fingerofdeath or Volley of Souls volleyofsouls

4) Repeat steps 2 and 3 until your damage boosting ultimate ability runs out and build to 100% adrenaline again

5) Repeat from step 1

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