Hello!
I came back to the game when the "Darkness Encounter" and the end-of-season hype started and I've had a good time grinding through the new content but noticed I was now stuck at 20/21 Triumphs for the seasonal Seal.
Turns out the required encounters for this specific triumph was removed before I even came back to the game :/
It kinda sucks that after spending quite a bit of time on this seal (the damn eeeeeeeeeeeyeeeeees) I'll still not get it because of something out of my control.
I was under the impression of seals that are [b]unattainable[/b] would be removed from the interface. Apparently not.
Now the easy fix would be just removing it, as it doesn't seem to have been a hard triumph to get while it was available. Hard fix, replace it with something else? Flawless dungeon? Something that is still doable today and tomorrow and until the season ends.