Mortal Shell 2: How to Beat The Monolith in the Obsidian Vault

Within Mortal Shell 2’s endgame dungeon, the Unfound Path, the Monolith is one of three guardian bosses. The Obsidian Vault route ends at this boss; defeating it is necessary to remove the corrupted tendrils across the zone’s center before the final boss, Zmey the Unbidden.

Quick answer: Chip away at the Monolith’s massive health pool and get clear of its leaping slams. Once its health drops below half, it fires beams and rotates them; keep circling, dodging when a beam crosses your path. When it falls, cut the red gland to unlock the route onward.

How to reach the Monolith in the Obsidian Vault

The Unfound Path only opens later in the campaign, after you have recovered enough Ova from the main Corrupted Gate bosses. The large platform in the middle of the dungeon starts sealed, and each of its three branches is guarded by a boss. The Monolith holds the Obsidian Vault branch; the others are Orrem, the Discarded Golem on the Bridge of Procession and the Malborn Offspring in Faithful’s Shelter.

Hand in all 168 Ova at the Gloom Siphon room in Marrow Keep to unlock the chasm. Drop into it to descend into the Unfound Path.

Cross the terrain past the central red pillar chasm and jump onto the launch pad. It carries you to the Chamber of the Forsaken Beacon, the first checkpoint inside the red cave.

Leave the cave onto the exterior ledge, take the shortcut drop, and step into the launcher lift to reach the next level.

Route to Brother's Court — The launcher lift that carries you up toward Brother's Court. Shown at 01:20 in Shark R’s video. Image: Playstack

Run through the temple halls, dispatching the serpent-like enemies along the way, and revitalize the Brother’s Court Beacon.

Cross the upper red-fleshed ramparts and climb the organic spires to bypass most of the enemies. This route drops you at the Obsidian Vault Beacon, directly outside the arena.

Walk through the archway to trigger the cutscene of the robed cultists and the standing monolith. When it transforms, the fight begins.

Boss Battle — Entering the Obsidian Vault arena to start the Monolith encounter. Shown at 00:25 in KaizoX Plays’s video. Image: Playstack

Loadout to bring into the fight

You cannot summon a spectral shell for the Monolith, so no ally bought with Glimpses can join you. Choose a shell and weapon with timing you know well. A swift dual-blade such as the Axatana suits this encounter, where staying mobile matters more than trading hits.

Mobility route: Genessa, the Wayward with the Axatana, staying agile and circling the arena.
Damage route: Obsidian Proxima shell with an Axatana +16 and the maxed Shrike Stone, whose ground plunge grants invulnerability frames while dealing 150 glyph damage.
Parry route: Tiel, the Acolyte for stronger dodges and extra damage to the boss’s back, backed by Tarstones that boost damage and break buildup.
The Grisha Remnant passive can draw aggro and add stagger while you reposition.

Build Setup — The Tarstones menu, where you set the damage and break stones before the run. Shown at 00:08 in KaizoX Plays’s video. Image: Playstack

Balance Patch 1 cut the Monolith’s base damage by 19% and its maximum health by 10%, and changed the timing of several attacks. Judge its movements as they happen instead of relying on an old dodge count, and read any Tarstone’s description before trusting outdated percentage values.

The Monolith’s attacks by phase

This towering stone block has an enormous health pool, making for a lengthy fight. It resists much of your damage, and its moveset shifts after its health drops below half. The fleshy center of its body repeatedly opens and closes; that opening provides your safest chance to attack.

Phase	Attack	How to handle it
Early	Jumping body slam	Clear the shadow beneath its landing point, then strike during its recovery.
Early	Swinging / walking swing	Dodge to the side as it pulls back; wait it out if it walks.
Below 50%	Beam fire	Keep sprinting, then evade as the beam crosses overhead.
Below 50%	Side roll	Dodge back and away; it rolls up to three times.
Below 50%	Rotating / 360° beams	Circle with the rotation and dodge on the beam’s timing.

Firearm u0026 Parry Mechanic — The yellow stagger bar below the health meter fills toward a free riposte. Shown at 01:23 in GuidingLight’s video. Image: Playstack

How to beat the Monolith

During the opening phase, keep moving and be ready for its leap. As the block rises for a ground slam, leave the darkened landing area; once it hits, move in for a few attacks before its next action. Dodging is safer than parrying, because its unusual animations make the parry timing difficult to judge.

Take advantage of the exposed center. Land two or three strikes while it is open, then create space again; with its large health pool, you don’t want to get caught mid-combo.

Phase 1 Parry and Riposte — Punishing the open core beneath the raised body during its recovery. Shown at 02:04 in GuidingLight’s video. Image: Playstack

When its health falls below half, prioritize constant movement. Its beams start at this point, so keep circling the arena rather than trying to hold a position. If you choose the parry route, block attacks to fill the stagger bar and earn free ripostes. Before the 50% riposte, get a shell back on, because a devastating beam attack from multiple directions follows.

When it spins while firing beams, check its rotation and move along the open lane. Dodge when the beam reaches you, not before; rolling early leaves you in its path when it arrives.

Attack in the pauses between beam volleys. Rush in for a few hits during these brief openings, or fire a sidearm during a genuine recovery at range. Use those windows to drain its remaining health and end the fight. Heal only once its action has finished and you’ve confirmed the lane will remain clear.

Reward and how to progress after the kill

Beat the Monolith to earn the Praise him! trophy and collect Gloom and the Monolith Fragment, an etched piece of obsidian. The Fragment cannot be used in combat; trade it for 5,000 Tar if you prefer to sell it.

Killing the boss alone does not complete the encounter. Walk over to the arena’s hanging red gland and cut it. The sever prompt appears, then a transition cutscene plays, confirming that the Obsidian Vault branch no longer contributes to the central tendril barrier. After clearing that branch, take on Orrem and the Malborn Offspring before confronting Zmey the Unbidden at the Unfound Path’s end.