Phase 1 & 2: Basic, clear packs of mobs. For phase 2, have a second tank separate the lizardman from the pets if you are having trouble staying up.

Phase 3: Raptor is an easy tank, however everyone, especially the squishy, needs to watch out for periodic scattered ground AEs. You have to act fast to get out in time before the spray of fireballs hit, and they hurt. Fire bad.

Phase 4: Melee mob MUST be separated from caster until 'brotherly love' buff no longer appears on them. At that point, the aim is to burn both down to zero at the same time, or as close as possible. Watch health and adjust DPS to either one as necessary. We usually tell ranged DPS to target caster, and Melee DPS to target Melee, although the melee boss will occasionally fire a small AE they need to get out of.

Phase 5: Dragon. Standard positioning for melees, not in front or behind, etc. All raid members move to get out of ground effects, and all Melees beware of his very painful point blank AE. You will have a few seconds to get out of range when you see him start to charge up. Tanks will also receive stacks of 'melted armor' debuff. Be prepared to swap out if you get too many of these. Off tank will want to pick up occasional (weak) adds to keep them off the squishies.

Phase 6: Profit!

-Bhune, League of the Ignoble Liver.
All mistakes or errors are to be blamed on beer.
Good luck.