This encounter requires some coordination but is not difficult to execute.
AEs:
The first thing to note is the big physical AE lands shortly after pull and needs to be jousted thereafter.
Other AEs include an Elemental and an Arcane but aren't particularly damaging, they just need to be cured.
Curse:
Yzlak will put a curse on three members of the raid at the same time. This will lock that player to it's current target i.e. if you were targetting a fluffy bunny that happened to hop past you, you will be locked on to "a fluffy bunny" until the curse expires/is cured.
Adds
Anyone remember Xygoz? In a similar fashion minature members of your raid (78 single up) pop at regular intervals. One healer, mage, scout, fighter. They automatically attack their raid counterparty. These need to be killed in around 30 seconds and can only be attacked by corresponding class archetypes i.e. if a scout pops, only scouts can attack it. If you don't kill these in time an add pops which, although manageable, makes life very difficult.
Strategy Overview:
Joust the Physical AE, cure every single curse that lands, kill the class adds fast enough, loot chest.
It's not difficult once you can coordinate the curse cures.
Hope this helps!