Im watching the run that the group I was in did a little bit ago beside Video 1. We're a few percent behind their group on the 100%-80% phase when their group phased it. The difference is they got a break bar 14s into the fight. We didn't get ours until 54s when she had 2% left until phase and after his group had already phased it.
The 80%-60% phase they had 5 mechanics which were. Swipe , Tail Slam, Hand slam, Swipe, Tail Slam all of which they could DPS through.
Our first 5 were Switch (movement and invuln), Tail (damage reduction), Tsunami, Tsunami Switch(movement and invuln) and it continues like that.
60%-40% phase
They get Hand Slam, Poison, Breakbar (20s into it) Swipe
We got Swipe, Tail Slam, Tail(damage reduction), Hand Slam, Switch(movement and invuln) ect. After a some more switches and another tail we got a break bar right at the end of the phase 110s into it and we took off the last couple of % of hp.
Our splits where we killed the 2-3 bosses were faster but it continues in this pattern for the next couple of phases until we fail in the final phase.