Serus Uriel instant attack

[fathom finch]

Summary: We were fighting Serus Uriel today in Mars dungeon for the quest and were one shot at some point because his usually slow wind up attack did just attack instantly. The indicator came up but the attack was directly hitting while the indicator did just start and kept filling.

Server: Burudeng
Character: S0nix511
Position: Mars Dungeon boss chamber
Expected result: Attack hits after visual indicator is filled
Actual result: Attack hits when indicator just started

[pliant rapids]

This bug is there since the update introducing dungeons and I don't think anyone from the dev team confirmed if this is indeed a bug or a mechanic.

It is worth noting that most (if not all) bosses are affected by this.