Bosses (Republic side):
Gark the Indominable: Summons adds (kill 'em) and then burn him down.
Drinda-Zel and Velasu: Kill one of them (we go with Drinda first.) After about 40% or so (didn't catch the exact percentage) he'll summon four turrets. CC/Kill them, and then resume burning Velasu. He'll respawn them - CC as many as you'd like and then murder him.
Tionese Bracers
Crystal Cutter Droid: Kill his friend, then kill him. Tank and spank. Blow cooldowns through the lasers.
Krel Thak: Do not hit him in melee while the blue shield is up. Do whatever you can to stun/knockdown/CC adds (Freighter/Mortar Volley/Sage Forcequake) because they hit like trucks,.
Loot: Energized Helm
Guid Patriarch (bonus): Tank and spank.
Loot: Tionese Ear
Commander Folex: Kill adds, Tank and Spank.
Serevin: Kill the healer first. Stealths periodically. Make sure to kick his abilities. Dark Explosion (may not be actual name) especially.
Loot: Columni mainhand.
The loot off of Serevin is the columi off-hand, not mainhand.
The biggest problem people have with this hard mode is Krel Thak. Heres a simple strat that (as of january 31st) still works. Outside of the hanger are several boxes stacked on one another, have your healer stand on the top box. Pull the boss straight back and fight him by these boxes. Make sure your healer isn't guarded and then when the adds come, they will aggro onto the heals and bug out due to not having a path to their target. Dont put any threat on them at all and they will just sit at the hanger entrence until the fight is over
After that its just a matter of dealing with shield probe.