"Sky Seer" unfairness (Atlas)

Hello,

well to make it short Sky Seer boss (tornado bird) is just so fucking unfair it makes me want to dodge his maps entirely (downside of being forced against boss every map starts to show)

Him casting a tornado that takes entire screen then doing his direct wind attack (while inside said tornado) which appears to do absurd damage is a bit too much, he managed to 1 tap my mercenary with 90 % armour 3k hp, then bit later did the same with my 6k shield lich- Definitely one of the rare boss I would objectively consider to be unfair