The Venomous Abyss

Entombed Sentinels Mythic Boss Guide

Entombed Sentinels
Purke
Last Updated: 23rd Sep, 2026

Raid Setup

Introduction

Welcome to our Mythic Entombed Sentinels guide, an earlier boss fight in The Venomous Abyss Raid in Midnight Season 2. This guide covers the fight mechanics and the strategy we recommend to defeat this boss on Mythic difficulty.


Fight Style: Council / Split raid on two bosses, one intermission

Recommended Setup: 2x Tank / 4x Healer / 14x DPS

Required utilities: Magic dispels, mobile immunities for orb pickups

Hero/Lust usage: On Pull

Easy Mode

  • Every Heroic mechanic is now lethal. Over-soaking Toxic Droplets orbs kill, the Toxic Droplet projectiles kill, too few on the red soak kills. Clean play matters more than damage here.
  • Shifting Protovenom (P1): 8 players get a circle. Remove it by moving into another player with a circle. Avoid touching a non-circle player, as it blasts and knocks back both. Pre-spread before every cast, and you may need to run to the other group to clear.
  • Intermission: orb counts only flash briefly then hide. Solution: players with 3-green stand still and ping themselves, players with 1-green hunt the players pinging and players with 2-green meet between the bosses. The Raid Leader can call from raid frames as a fail-safe.
  • Failing the mini-game usually wipes you, it floods the room with red puddles.
  • Rotate mobile immunities to grab green orbs on hard sets (right before intermission, or when orbs land in the red puddle).
  • Give the green add extra priority on every 2nd set, it spawns right before the intermission.
  • Keep the room clean with a set red-puddle placement pattern (see strategy picture).
  • If DPS is tight, balance both bosses' HP before the intermission by swapping players around, not by stopping DPS.

Mechanics

Shifting Protovenom Mechanic Icon

Shifting Protovenom

Entombed Sentinels contaminate 8 random players with a prototype venom, each getting a circle around them. Coming into contact with another Protovenom player neutralizes them harmlessly, but colliding with an uncontaminated player triggers a Protovenom Eruption. This is a ticking Plague DoT until cleared, so affected players still have to resolve it after pairing.

Be careful with this mechanic and don’t panic, especially close to the bosses and melee, as it can lead to a chain event of people being knocked into each other and killing players.

Protovenom Eruption Mechanic Icon

Protovenom Eruption

The failure state of Shifting Protovenom. If a contaminated player touches an uncontaminated one, both take heavy Plague damage and get knocked away.

This is why the raid pre-spreads whenever Protovenom is out, a stacked raid eating an eruption loses several players at once.

Strategy

Sentinels is an early spike in difficulty, mostly because of how punishing the fight becomes the moment people start making mistakes. All the Heroic mechanics are now genuinely deadly:

On Heroic you could make quite a few mistakes and still survive. On Mythic, most mistakes will quickly add to the wipe count, so the Heroic guide's base fight still applies, it’s just much less forgiving.

Both sides always play the same, so it's up to you which side starts with Green/Red boss, but you have to perform a swap after each intermission.

Phase 1

The main Mythic addition is Shifting Protovenom, which gives 8 players a circle:

  • Two circle players touching each other clears the venom harmlessly.
  • A circle player touching someone without it triggers Protovenom Eruption, blasting and knocking back both, and you still have to clear afterwards.

Because of this, you pre-spread every time it's applied, since a stacked raid all getting hit by an eruption can kill several players at once.

Note: Depending on who Shifting Protovenom Circles get applied to, you may have to run to the opposite group to find a partner to clear with.

entombed sentinels mythic shifting protovenom circles

A few more Phase 1 details to understand and focus on:

  • Toxic Droplets: rotate mobile-immunity players to run over these on the hard sets. The hard sets are the ones just before the intermission, or any set where most droplets spawned inside a Blood Venom puddle. A normal pickup there gets people killed, an immunity does not.
  • Venom Coagulation: give the slime extra priority on every 2nd set, since it spawns right before the intermission and you don't want its Contaminate pulses adding raid damage during the mini-game.
  • Floor management: keep the room clean with a set pattern for placing the Blood Venom puddles. A messy floor is what turns a recoverable Protovenom or a bad soak into a wipe.

entombed sentinels mythic blood venom puddles

If you play this mechanic badly, you can quickly run out of room to move around safely, making the other spread mechanics more challenging to do.

Ideally after the second intermission, you should still have most of the room available.

entombed sentinels mythic blood venom puddles after intermission 2

If you're struggling with DPS, get both bosses close to equal HP before the intermission for Vitriolic Stasis. Don't do it by stopping DPS, do it by swapping players around for more even damage, so you keep your total output higher while still lining up their health.

Intermission

During Vitriolic Stasis, on Mythic Difficulty, you only briefly see everyone's Helical Toxins orb count before it gets hidden. Sounds like chaos, but the solution is simple and reliable:

  • 3 green orb players: stand still and ping yourself with a warning.
  • 1 green orb players: hunt for the players pinging themselves.
  • 2 green orbs players: meet between the two bosses.

entombed sentinels mythic vitriolic stasis intermission

That covers every combination cleanly. As a fail-safe, if someone still hasn't cleared, the raid leader can call people out from raid frames, since the frames show who has how many orbs.

Take it seriously, a failed mini-game leaves players with Cultivated Burst, which usually wipes the raid by covering a large portion of the room with the red puddle.

Closing out the Fight

Once you clear the intermission cleanly, the fight loops back into the Phase 1 pattern until the bosses are down.

There's no new trick at the end, so the kill just comes down to repeating what you've been doing: pre-spread for Protovenom circles, keep the floor clean, use immunities for the hard Toxic Droplets sets, and calmly solve the mini-game the same way every time. Do this consistently and the Sentinels fall.