Ergo Sum Catalyst: How to Get It and Finish the 500 Kills

The Ergo Sum catalyst drops from Excision, the final mission of The Final Shape. In Bungie's words, Excision on Grandmaster "rewards the Ergo Sum catalyst". Normal Excision can drop it too, as a chance drop.

Excision takes up to 12 players. Players can join a run that is already in progress.

You need The Final Shape and Ergo Sum itself before the catalyst matters. Once it drops, it slots into the sword and the kill counter starts.

The catalyst gives Ergo Sum the Transcendent Steel perk. In the game's words: dealing damage with a Transcendent grenade grants Ergo Sum ammo.

The Transcendent grenade comes from your Prismatic subclass. Each grenade hit puts ammo back into the sword.

Ergo Sum already leans on Transcendence. Its fixed trait, Transcendent Duelist, makes the sword collect less ammo. In return, its final blows speed up your Light and Darkness mastery. The sword also hits harder while you are Transcendent.

The catalyst closes that loop. Transcendent grenades refill the ammo that the trait holds back.

The catalyst counts targets defeated with Ergo Sum. The goal is 500. Transcendent Steel switches on only after the count is done.

• Pick dense, low-difficulty rooms. Weak adds die to 1 swing, and every kill counts.
• Play Prismatic. Transcendent Duelist adds damage while you are Transcendent, so the grind goes faster there.
• Keep special ammo coming. Ergo Sum is a special ammo sword, and the trait makes it collect less.
• Stay in a fireteam. Waves die faster and the next room opens sooner.

Counting stops at 500. Ergo Sum is then masterworked and Transcendent Steel is live.

Every other catalyst and its unlock sits on our exotic catalyst list.

Ergo Sum is an Exotic sword from The Final Shape. It uses special ammo.

• 1st copy. Finish The Final Shape campaign. The Destined Heroes quest then rewards Ergo Sum.
• More copies. Pathfinder in the Pale Heart pays Ergo Sum up to 2 times a week per character. Grandmaster Excision drops it too.

Every copy rolls its own setup:

Part	Possible rolls
Element	Arc, Solar or Void
Exotic trait	1 of 8 traits borrowed from other Exotics, such as Wolfpack Rounds, Arc Conductor, Stormbringer or Insectoid Robot Grenades
Frame	A Sword frame, such as Vortex, Caster or Wave
Fixed trait	Transcendent Duelist on every copy

Monument of Triumph went live on 9 June 2026 with Update 9.7.0. Bungie calls it the final release for Destiny 2.

Bungie announced 25 new catalysts for Exotics that had none. Ergo Sum already had its catalyst, so the catalyst keeps its Excision source.

From 18 to 25 June 2026, a community challenge asked for 250,000 Excision clears. Players reached the goal early and unlocked the Intrepid Pearl emblem.

On 29 October 2026 Bungie set out its next steps. The 1st unvaulting pass brings back 4 older campaigns. Bungie plans its next major Destiny news for February 2027. The full plan is in our Un-Vault guide.

None of this moves the Ergo Sum catalyst. Grandmaster Excision is still the clear that rewards it.

Grandmaster Excision needs a full team that knows the fight. A Pro team clears it on your account, and the catalyst drops at the end.

• Grandmaster Excision. The clear that rewards the catalyst. Self-play is an option on the page.
• The Final Shape campaign. For accounts that still need it before Excision.
• Custom farming. For the 500 kills, or for extra Ergo Sum copies from Pathfinder.

Each card prints its live price. Tell the chat which part is left: the drop or the kills.