(spoiler) Final fight is ridiculous...
The final fight is just really buggy all around. I was having the rocks not rendering on my screen by the time they hit me out of the sky, the avatar doing attacks that he wasn’t supposed to do in that phase (leystorm while I was on the rift converting Rytlock… it pulled me off the rift and killed me), the platform with the rift on it disappearing after a wipe so you couldn’t do it (and had to die and break another piece of armor to try to reset it), the final rift not breaking the bosse’s shield (and then the rift disappears) leaving the boss invulnerable and unbeatable, etc.
You can tell it was not playtested very much. Probably only by the devs who designed it who knew exactly what to do so they never died (many of the bugs were triggered by wiping and restarting)