An unknown Titan that first appeared at the 2060 Mingdeng Ritual. Resembling a beast, this Titan can release bursts of Thermal Energy when in the Foehn state.

Fiend is a set of Titan bosses with variants in different elements. This guide covers the Fire-element variant, commonly referred to as “Fire Fiend.” Compared to its Icy sibling, Fire Fiend’s ranged attacks are much less threatening at the cost of it really not respecting your personal space. It can get messy.

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Behaviour and Attacks

Fire Fiend technically has three “phases,” but they all play the same.

Basic Attacks

Pounce

Fire Fiend jumps towards you, dealing AoE damage and knocking you back on hit.

It can also perform a charged version of this attack, which is aimed more directly at you. At higher difficulty levels, the range of this attack’s effects is extended to the entire map, and will also apply Burn if you’re hit. These attacks are generally very telegraphed, so time your dodge well to avoid getting whacked.

Flaming Columns

Fire Fiend marks a series of circular areas in a grid pattern, then summons columns of flames from them after a delay (hence the name). Being hit by the initial summoning will stagger you, but you can freely pass through them afterward without being interrupted. You still take damage though, which can be useful for reducing your health in a controlled manner if the weekly Neural Sim modifier reduces your damage while over 50% HP. At higher difficulty levels, these columns last longer.

Laser Beam

Fire Fiend fires a laser that sweeps from left to right. Being hit will knock you back. When dodging this attack, roll towards the left, in the opposite direction that the laser is moving. This will make the timing window much more generous, preventing the odds of you getting hit.

Rear Barrage

Fire Fiend launches a field of mines. After a duration, the mines detonate. Touching a mine or being in the radius of its detonation will deal damage, but will not stagger. At higher difficulty levels, more mines will be summoned, and they will detonate sooner. This is identical to the attack that Ice Fiend does, so the advice here is the same:

Casual players: If you can dodge backwards, that’s usually the fastest way to get out of the minefield. I’d recommend just timing your dodges to avoid the initial and follow-up damage, though.
Speedrunners: If it won't kill you, just tank the hits and use it as an otherwise-free DPS window.

Missile Volley

Fire Fiend summons a cluster of missiles that launch towards you with mild homing capabilities. It’s still a pretty easy dodge or sidestep, especially if you can keep your distance. Make sure you do avoid most of the missiles though, because eating all of them will drop your health pretty low if it doesn’t kill you outright.

Swipe

Fire Fiend swipes twice with its front paws, then jumps forward, dealing damage and knocking you back if hit. Unlike the otherwise-identical attack that Ice Fiend can do, Fire Fiend will then summon a flaming column and pounce on you one more time after its initial attacks at higher difficulty levels, so even if the first two melee attacks miss, be respectful of the pounce attacks that come after.

HP Triggers

At 70% and 40% HP, Fire Fiend will turn invulnerable and summon three pillars. These pillars must be destroyed in order for Fiend to exit its invulnerable state. At higher difficulty levels, Fire Fiend will also summon several flaming columns.

These pillars can be damaged and destroyed as soon as they begin to be summoned, including while they’re still in the ground. Getting the timing down can take practice, but is a pretty free time save. If the pillars aren’t destroyed fast enough, then a large map-wide explosion will occur, dealing huge damage and knocking you back. Like with Ice Fiend, you get a very generous amount of time to break the pillars, so don’t worry too much about that.

These HP triggers can’t be cancelled or skipped, so the best you can do is to get it over with as quickly as possible.

The pillars can be quickly destroyed all at once if you have a source of AoE damage. For example, Haru - Absconditus can basically one-shot the pillars while they’re still in the ground.

Operatives like Enya - Exuvia can also cast their skills to quickly chunk out the HP of the pillars, after which you can swap back to your main DPS to finish them off.

Strategy

HP: 3,498,354

Fire Fiend can be very annoying due to its tendency to get right in your face. However, if you can get a run where this doesn’t happen, you’ll find that it’s actually not very threatening at all. Your actual experience will likely be somewhere in the middle, so take advantage of the freebie attacks it throws at you because you never know when it’ll decide to violate your personal space.

Okay, I’m just going to be real with you. Team building and general strategy is basically the same as with Ice Fiend, with only two major differences aside from its moveset:

1. It has a heck of a lot of Thermal resist
2. You can Freeze it

This means that Thermal DPS operatives are obviously not recommended here, while Freeze supports like Lyfe - Wild Hunt get some extra utility. Keeping that in mind, you can just read Ice Fiend’s strategy section and it’ll apply here basically just as well.