In a hotfix about an hour ago, Blizzard nerfed Phase 2 of Mythic Fyrakk.
About an hour ago, a hotfix was applied that nerfs the Colossus by 12%.
Colossus exploding at 100 energy and killing the raid was one of the #1 causes of wipes for both Echo and Liquid while progressing on this boss. Having to control the add wave while dealing maximum cleave and single target damage to the adds was a difficult part of the fight.
Due to this change, Echo has technically reached Phase 3 for the first time but have seen no mechanics due to the wipe condition being triggered.