Break the Unbreakable is the fifth Quest in Act 5 Chapter 4: Cornerstone, and was released on December 15, 2017.
It contains 6 paths and ranges from 9 to 13 Opponents per path. This Quest, like the remainder of the Chapter, has a locked camera view, and its portals contain hints for their respective paths - Power, Resilience, Immunity, Rage and Poison & Bleed.
It is preceded by 5.4.4: Do the Impossible and succeeded by 5.4.6: Fight the Power.
Nodes[]
Global 
[]
| Name | Effect(s) |
|---|---|
| Champion Boost | +300% Attack & Health |
| Iso-Infused | +50% Attack and Health |
| WARNING | A third Special Attack has been activated! |
- All Global Nodes are removed immediately before the boss fight.
Paths[]
Local 
| Path | Name | Effect(s) |
|---|---|---|
| Immunity | Immunity | Immune to Debuff effects. |
| Rage | Fury | When Struck, the Defender has a 10% chance to trigger a Fury Buff for 8 seconds, granting +100 Attack. |
| Poison & Bleed 1 | Biohazard | When struck, 20% chance to inflict Bleed, dealing 100% of Attack as direct damage over 7.50 seconds. When Blocking an attack, 50% chance to inflict Poison, dealing 100% of Attack as direct damage over 7.50 seconds. |
| Poison & Bleed 2 | Caltrops | Dashing backwards against this enemy causes you to Bleed for 6 seconds. |
| Power | Cornered | Whenever a damage over time Debuff is applied to the Defender, they gain 100% more power for the duration of that Debuff. |
| Resilience | Explosive Personality | When the Defender Blocks an attack, they activate an Armor Up Buff, boosting Armor by 25%. Upon reaching 5 stacks of Armor Up generated by Explosive Personality, Armor Up stacks explode and remove 25% of the Attacker’s Max Health. |
Boss: Mephisto []
Local
| Name | Effect(s) |
|---|---|
| Fire of Hades | At the start of the fight and every 30 seconds, Mephisto activates his Aura of Incineration for 10 seconds. |
| Health | +200% Health |
| WARNING | A third Special Attack has been activated! |
| Champion Boost | +300% Attack & Health |
| Iso-Infused | +50% Attack and Health |
Dialogue[]
Doctor Voodoo: Anthony, anything to report?
Iron Man: Collection is going smoothly. We’re getting word of folks bumpin’ up against the Grandmaster’s goons, but nothing serious yet.
Black Panther (Civil War): Still, we should be at the ready. Once he catches wind, we’ll have a real fight on our hands. Iron Man: For now, best we can do is keep moving and stay focused.
- Transmission #1 - Upon starting the Quest
Iron Man: Here’s a loaded question: does anyone have the slightest clue how we’re going to put these back together once we have ‘em all?
Doctor Strange: Magic, I think. Iron Man: Magic. That’s it? Just “magic?” Doctor Voodoo: It’s as straightforward as it sounds, Anthony. Iron Man: Wizards…
- Transmission #2
Nebula: Reports of major pushback coming from all Battlerealm sectors.
Civil Warrior: Looks like the Grandmaster’s counterattack is in full swing. We need to hustle! Black Panther (Civil War): Hopefully the others can hold out. We’re so close!
- Transmission #3
Mephisto: Ahh, the Summoner and the merry band of dissenters. I’ve barely begun my tenure as a competitor in this Contest, and you’re already getting in my way. Mephisto: What’s wrong? Not interested in a little fun?
Kang the Conqueror: Bah! Amateur! The only true contenders in the Battlerealm are the Summoner and I, and I will not have some overgrown Halloween decoration prevent my revenge! Iron Man: Kang sure has a one-track mind… Mephisto: Bold words, “Conqueror!” Let’s see you prove your worth! Kang the Conqueror: You will know your place, demon!
- Transmission #4 - Before fighting Mephisto