Hati and Sköll are powerful
Fenrir Bosses that reside in the realm of Asgard, they are summoned from the World Boss Terminal.
Due to being out in the open there is a high likelihood of Creatures interfering with the fight.
Both Bosses also have their own set of abilities to complicate the fight with Hati specifically summoning Fenrir Minions and Sköll utilizing an AoE Fire Howl attack that also summons a Spirit version of itself to charge in a straight line.
Hati can inflict Moonfreeze and Sköll can inflict Sunburn, both of which can severely wound the affected tamed creature's health.
The giant rock pillars surrounding the arena works some kind of barrier, the bosses reset their hp bar if they touch the point.
Finally if the player chooses to target Hati first then be aware of the fact that despite Hati's death the Fenrir Minions it spawned in wont die with it like typical bosses and will only die if killed or when Sköll also dies.
They have the largest "arena" with the fight taking place in the open fields of Asgard and as such increases the variety of usable tames without the restriction of arena size.
Also depending on which Boss is taken out first will make the boss fight easier as Hati is the one capable of summoning Fenrir to aid them and Sköll can utilize devastating attacks.

Fought in Asgard. The article's terminal coordinates duplicate
Steinbjörn's Jotunheim figure, so no coordinate is recorded here rather than a wrong one.
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