The event is timed, if you don't finish it in 22 minutes (?) the raid will be DT'd by brekt.
Several old bosses, all with "upgraded" versions of the spells they cast during their original events.
Zun - Event starts with him, has an ae around him that silences/massively slows. Can be overcome with monks using their spell negation disc and pets. When he reaches 95% or so the ae will drop and he will be moveable, the Ikaav will also go active at this point. On his death, AMV will become active.
Ikaav - The same as she is in tacvi, despawns every 15% or so, will FD and spawn small snakes, kill the snakes to make her stand up. Will cast Ikaav venom dot if the adds are not killed fast enough, minor dot. On her death, Taskmistress will become active.
AMV - Has mark of death DT ae, this version is corruption cure. Sizable HP, using discs on him and taskmistress are best in terms of saving time on the overall encounter. On his death, the Syncanar (sp?) spawns but is not engageable until all the other bosses are dead.
Taskmistress - Nothing special, throw her in a corner and kill her. Mostly just in the event to slow you down with her large hp. On her death the Syncanar becomes engageable and adds will begin to spawn.
Syncanar - Melee immune, is only damageable 20% after a successful emote execution. Pets can damage him, spells land when his shield is down. The trick here is to follow the emotes that go off from the pyrilien and geldrian they call a fire/ice nuke pattern that you must follow. EG if the pattern is Fire,Ice,Fire,Ice then you need to hit the pyrilien with a fire nuke once, the geldrian with an ice nuke once, fire nuke they pyrilien again, and then hit the geldrian with an ice nuke again. If done successfully the Syncanar will emote and you will be able to land spells and damage him another 20%. The pattern is random each time, so easiest to have a couple of wizards watch for it. If the emote is failed and nukes are not done fast enough or out of the specified order, you must wait for them to emote again. The wait is pretty long so too many failures this late in the event will result in you running out of time and wiping. On his death, a chest will spawn.
Adds - Two types of adds spawn during the syncanar phase, horrors and golems, golems can be charmed, horrors can be rooted/snared. They have too much hp to kill at the rate they spawn, easier to park them in an area away from the raid.