Underkeep Boss Guide: Named Foes, Optional Fights, and How to Prepare

Which Underkeep This Boss Guide Covers

This guide is about Underkeep, the first-person, turn-based dungeon crawler from Rake in Grass on Steam app 2411200. It is not about The Underkeep, a Final Fantasy XIV dungeon that shares the name, and it is not about the World of Warcraft delve of the same title. If a page you are reading mentions Gargant, Soldier S0, Valia Pira, item level 705, or a four-player duty, it is describing a different game.

That distinction matters more here than on most topics, because "Underkeep boss" is a search phrase where the wrong game currently outranks the right one. Everything below stays tied to app 2411200.

What Official Underkeep Sources Confirm About Bosses

Two official sources carry the weight here, and neither is a strategy document.

The first is the store description, which lists "hidden alcoves, fake walls, optional bosses and puzzles" as part of the game's design. That confirms optional bosses exist as a category. It does not publish a count, a floor list, or a loot table.

The second is the official Steam achievement list for app 2411200, which names specific fight targets through its goal text. Those names are the closest thing to an official roster:

Read that table for what it is: proof that a bandit chieftain, three High Clerics, and a dragon-related decision exist in the shipped game, plus a level-5 and level-10 progression check elsewhere on the list. It is not proof that any of them is optional, mandatory, or a chapter-ending encounter.

The Wider Roster Players Are Documenting

A current player-written guide for app 2411200 fills in more detail. "Underkeep Player's Guide" by VoidEngineer, updated November 6, 2026, includes a spoiler-tagged "Bosses and named foes" section that lists the Rat Queen, Mother of the Warren; Arachneira; Scourge of the Tunnels; the Orc Chieftain; the Bandit Chieftain; Dreadcoil of the Deep; the Frog King, Last Crown of the Mire; Obula; the Skeleton King; Fangspire; the Mud Ooze; and the Thing, with several more deeper in.

That list lines up with the official achievement text where the two overlap — the Bandit Chieftain appears in both — which is a good sign for its reliability. It is still player documentation, not a developer publication, so treat it as a reference roster rather than a guarantee. Names, order, and optional status can change with a patch, and the guide's author explicitly hides late-game names behind spoiler tags rather than claiming a complete count.

The practical takeaway is narrower than a tier list: Underkeep has more named fights than the official material names, and the verified core is the bandit chieftain plus the three High Clerics.

How Boss Fights Differ From Corridor Fights

Underkeep resolves combat in discrete rounds, and the same rules apply whether you are clearing a corridor or standing in front of a named foe. The differences are pressure and length, not a separate system.

• One action per hero per round. Potions and inventory items do not consume the action, so a healing potion is a free stabilizer rather than a wasted turn.
• Rows decide who can hit what. Melee needs the front row unless the weapon has Reach. Most enemies hit your front row, which is why the tankiest adventurer belongs there.
• Stamina and mana are separate budgets. The store description calls both out directly. A long boss fight is where a party that spent everything on the first three rounds runs dry.
• Status effects decide fights. Stun, freeze, blind, bleed, poison, burn, and paralyze all have counters. The player-written guide's boss advice is blunt about this: check immunities on the first turn, because many bosses ignore stun.
• Marks concentrate damage. Hunter's Prey and Mark the Dead both raise the damage a single target takes, and the player guide recommends keeping one on a boss for the whole fight.

Preparation That Survives an Unknown Roster

Because no official boss list exists, the reliable preparation is party-level rather than encounter-specific. These steps come from the player guide's boss section and from the game's own store description:

1. Rest and save before an obvious boss room. Rest restores HP, mana, and stamina for the whole party and consumes food, so arrive with a stocked pantry.
2. Carry cures, not just healing. Bleed, burn, poison, stun, and freeze each have a specific remedy, and a boss that stacks two of them can outpace raw healing.
3. Bring one source of armor bypass. Armor is subtracted from every physical hit, so armored bosses punish pure weapon damage. Void Lance ignores defenses outright, and Slice and Dice and Riposte ignore armor.
4. Keep a revival reserve. Fallen heroes come back at a Revival Statue for gold, which makes a gold buffer part of your boss kit.
5. Use the map before the door. The automap supports custom markers, and the player guide treats "mark the suspicious wall and come back" as standard practice for optional content.

Optional Bosses and Secrets

The store page's promise of "hidden alcoves, fake walls, optional bosses and puzzles" is the only official statement on optional fights. A developer reply in a Steam discussion thread (posts dated February 27–28, captured 2026-11-06) adds that hidden buttons and passable walls exist, that hints are placed so secrets are not unfair, and that secrets are not meant to block main-story progress.

That combination suggests optional bosses sit behind exploration gates rather than in the critical path. It does not name them. If you are hunting for a specific optional fight, the honest sequence is: clear the main route, then sweep each floor for fake walls, buttons, and alcoves with the automap open.

Boss FAQ

How many bosses are in Underkeep? There is no official count. The store confirms optional bosses exist, official achievements name a bandit chieftain and three High Clerics, and a current player-written guide lists a dozen or more named foes for reference. Treat any exact total as player data.

Is the Skeleton King a boss in Underkeep? A current player-written guide lists the Skeleton King under "Bosses and named foes." No official page names it, so the safe wording is that it is player-documented rather than officially confirmed.

Are Gargant, Soldier S0, and Valia Pira Underkeep bosses? No. Those three belong to a Final Fantasy XIV dungeon also called The Underkeep. They have their own mechanics, their own item-level requirement, and no connection to Rake in Grass's game.

Do I need to grind levels before a boss? The achievement list caps its explicit progression checks at level 5 and level 10. Reaching a boss with your party's key skills unlocked matters more than raw levels, because skills carry the status effects and armor bypass that boss fights demand.