Final boss: Focus boss. 1 dps on ads. Kill 3, wait for boss' rancor to fade, it's a giant emote on your screen, you can't miss it. Then kill 3, then wait, then 3, then wait, then 3, then wait, then 3, then wait, then 3, then LB boss. Then win. Easy right?

Again, if you have problems with this instance you are bad. It's a dps instance, of you can't dps, go be a healer.