Time's Vengeance insta-cooldowns all abilities and makes guardian weapons deal tons more damage. While holding the relic, it allows for a continuous barrier to stay up so guardians can safely kill Atheon from inside in the allotted time. The only supers going off should be Ward of Dawns for weapons of light bonus damage, and Golden Guns for one-shotting the supplicants for a safer retreat after Time's Vengeance goes away.