How to Defeat The Underpin in Season 2: Boss Strategy & Rewards Guide

The Underpin is a seasonal pinnacle boss introduced in The War Within Season 2 that you can defeat in the Demolition Dome delve for rewards.

The entrance to The Underpin's delve is located at the upper level of the Demolition Dome. Demolition Dome is located in Undermine at /way #2349 52.38, 9.42.

The Underpin's delve is available in two difficulties:

• Tier ? unlocks when you clear a Tier 7 delve with lives remaining in Season 2.
• Tier ?? unlocks when you clear a Tier 10 delve with lives remaining in Season 2.

The recommended item level for Tier ? is Item Level 620.

You should use the following two WeakAuras for Brann:

• Dwarven Medicine Tracker: Ensures 100% uptime on Dwarven Medicine to build stacks indefinitely.
• Brann Bronzebeard Interrupt Tracker: Shows you the cooldown on Brann's interrupt so you do not waste yours!

As for curios, you can pick Mechasaur EZ-Build Kit for taunts combined with L00T RAID-R for increased damage taken. However, keep in mind that your curio choice is not that important while facing The Underpin.

Do not forget to download Deadly Boss Mods to stay on top of when The Underpin casts his abilities.

The Underpin uses the following abilities on Tier ? difficulty:

• Crush — The Underpin attempts to Crush his enemies with his the full force of his mech, inflicting Physical damage to players caught in the area and stunning them for 4 sec.
• Time Bomb Launcher — The Underpin launches 5 Puntable Time Bombs nearby.
• Flamethrower — The Underpin attempts to set his foes ablaze, inflicting Fire damage every 0.5 sec to players within 15 yds in front of him.
• Signal Cronies — The Underpin summons 3 minions to assist him who use two abilities:
  • Shoot: Cronies shoot at you, dealing unavoidable damage.
  • Molten Cannon — Underpin's Croney powers up his Molten Cannon and fires a powerful orb of molten lava at a player's location which inflicts Fire damage and knocks back all players caught in its path.
• Recharge — The Underpin casts a shield that you must DPS down quickly. Otherwise, he will heal for roughly a fourth of his entire health pool.
• Oil Spill — Disrupting Underpin's attempt to recharge damages his mech causing it to spill oil nearby every 0.5 sec for 5 sec.

The key to defeating The Underpin is to avoid his Crush at all times. You will see a circle where Crush is cast. Avoid standing there, as you will be stunned for 4 seconds. Avoid his frontal cone Flamethrower ability at all times.

Periodically, The Underpin will cast several puntable bombs on the ground and adds. The goal is to play bowling with the bombs and shoot them into the adds. The adds have a basic Shoot mechanic that deals unavoidable damage and a Molten Cannon that fires an orb down a given path instantly killing you. You want to prioritize killing adds as soon as possible with the bombs, because they will not despawn and you will end up having to avoid a ton of stuff.

It is recommended to fight The Underpin near walls or the entrance, so when adds spawn, they are stacked up together nicely, and you can quickly defeat them with a single bomb.

At every 20% health, The Underpin will cast a shield for 10 seconds that you must quickly DPS down. If you do not manage to do that, he will heal for 25% of his health via Divert Energy to Shields. Breaking the shield casts Oil Spill, causing oil to spill nearby. The spills persist throughout the fight, so you do not want to stand in them.

Defeating The Underpin in Season 2 provides achievements that grant various rewards:/p>

• Let Me Solo Him: The Underpin: Defeat The Underpin in his lair on Tier ?? alone, before the release of the next season of delves. Rewards the Delver's Gob-Trotter Schematic: Gold tint for the Delver's Gob-Trotter mount.
• Breaking the Bank: Defeat The Underpin in his lair on Tier ??, before the release of the next season of delves. Rewards The Real Deal title.
• My New Nemesis: Defeat The Underpin in his lair before the release of the next season of delves to get Golden-Gob Propulsion Rig (Cosmetic Back).
• The Hataclysm: Ask Brann to change his hat ten times after recovering it from The Underpin during The War Within Season 2.

Here is the Delver's Gob-Trotter Schematic: Gold in its full glory.

Golden-Gob Propulsion Rig is a Cosmetic Back and here is a preview of its in-game model.

Delves received many important updated in Season 2, including new rewards! We recommend you to read our updated guide for an overview of all the latest changes.