i think that was just due to the frost proc on hit 1 of that final crit. you can see how its damage total of 5900 is less than the earlier 6442 damage frost-proc'ing crit at 0:43 where RKR was actually active. the other RKR crits throughout the fight that don't proc frost land closer to the 3000 damage mark
Why did the last crit, without RKR, do so much more damage than the others?
i think that was just due to the frost proc on hit 1 of that final crit. you can see how its damage total of 5900 is less than the earlier 6442 damage frost-proc'ing crit at 0:43 where RKR was actually active. the other RKR crits throughout the fight that don't proc frost land closer to the 3000 damage mark