Protheon

Protheon, Modular Mind is the awakened Vex Mind buried beneath the surface of Nessus in Arcadian Valley. It was exposed by the Cabal's drilling operations. It is the final boss of The Inverted Spire Strike, whose objective is to destroy it.

Overview

The Mind is reached by going down past the Cabal's drill, along the dig site. The Red Legion had unearthed it after taking Nessus, and a Guardian fireteam later destroyed it when the Red Legion tried to capture it.

Boss fight

Protheon's fight is split into three stages. Descriptions label them by form (Void, Solar and Arc).

• Void stage: Protheon roams the arena, fires its Torch Hammer, teleports and summons Vex reinforcements. Getting too close can trigger a Temporal Shockwave that can kill a player instantly. When it loses a quarter of its health, the floor dissipates and the team drops to the next arena.
• Solar stage: Protheon holds the centre and fires an Arc Slap Rifle. It slams the ground to create fire that drains health, and Goblins and Hobgoblins arrive as its health falls. After another quarter of health, the floor dissipates again.
• Arc stage: For the first half, Protheon attacks from range with its Slap Rifle and grenades that blind players, while Goblins and Fanatics flank the team. In the final quarter, it enters a berserker rage and charges, stomping out more Temporal Shockwaves until it dies.

On lower difficulties players can sometimes force it to skip a phase.

Reprise

The Inverted Spire was reworked as a Reprise under Episode: Revenant, set in The Cistern on Nessus. Its enemies are Compelled Vex, and Protheon returns as one of its bosses alongside Precursor Nexus Hydras, Compelled Koresian and Harrowed Frame.