2.5 Protheon

Overview

After dropping into the Spire cavern, the party will have a moment to catch their breath while they descend further into the area. Dropping about 40 feet into an arena, the party dispatches a couple of Vex Harpies. After the Harpies have been dispatched, Protheon, Modular Mind will appear and begin combat with the party. The party will be able to see that Protheon has integrated the final artifact into its chassis.

Encounter

Enemies

Rank-and-File

The encounter opens with 4 Vex Harpies that must be defeated to summon Protheon. Otherwise rank-and-file enemies are scarce in this encounter. Protheon can summon Harpies in Phases 1 and 2, and Fanatics in Phase 3. The number that can be summoned is listed as part of Protheon's stat block.

Boss

Protheon, Modular Mind, is a Gargantuan Vex Minotaur frame empowered by the Vex to protect the Inverted Spire from the Cabal drilling operation. Combatively, it operates very similarly to a Minotaur with a few additional mechanics.

Mechanics

The Protheon encounter is split into three distinct phases 3 phases based on the boss' health pool; Void Phase, Solar Phase, and Arc Phase.

Void Phase

During the first phase, Protheon exists in its Void form. In Void form, its speed is 20 feet. It begins its turn by Teleporting to one of the 3 predetermined attack locations and makes attacks using its Torch Cannon. As a Reaction once in this phase, Protheon can summon two Vex Harpy enemies to join the fight. When its Void form health pool is reduced to 0, it uses an Ultra Action to Reconfigure to its Solar form.

Solar Phase

Protheon's second phase is its Solar form. In Solar form, its speed becomes 0 feet and it gains a damage point of 5. It primarily attacks with its Solar Slap Rifle, and unlocks its Integrated Conduction ability which it uses immediately upon each recharge (5-6 on 1d6). Additionally, once during this phase, it can use a Reaction to summon two Vex Harpy enemies. When the Solar form health pool is reduced to 0, Protheon uses its final Ultra Action to Reconfigure into its Arc form.

Arc Phase

Protheon's final phase is its Arc form. In Arc form, its speed becomes 40 feet and its Solar form damage point is removed. It primarily attacks with an Arc Slap Rifle, and unlocks its Bull Rush ability that it uses immediately upon each recharge (5-6 on 1d6). Additionally, once during this phase, it can use a Reaction to summon 4-6 Fantatic enemies. When the Arc form health pool is reduced to 0, Protheon is considered destroyed.

Reconfiguration

As an Ultra Action, Protheon changes its form while also relocating the battle arena. This involves dematerializing the floor from underneath the party and dropping them a considerable distance into another chamber. During these arena transitions, each member of the party must make a Dexterity (Acrobatics) check to maintain their orientation and successfully break their fall.

• Rolls >15: No damage
• Rolls 11-14: 1d6 bludgeoning damage
• Rolls 8-10: 2d6 bludgeoning damage
• Rolls <7: 2d8 bludgeoning damage, knocked prone, considered Stunned.

Rewards

Scavenging Protheon's destroyed frame, the party can retrieve the following rewards.

• War Artifact
• 3,300 glimmer
• 10 Microphasic Datalattice
• 3 Fine engrams

Parent Plot

2. Inverted Spire