My guild is still progressing on spine(Lame I know but for casual it's not that bad ^^). 25man that is. We are also getting overrun by the bloods but the main tank came with suggestion which we will try next week. We are not rolling the boss during 2nd plate which causes to get a lot more bloods spawn, so we may actually roll once or twice to prevent it. Try it with your group aswell, might work. AOE bloods, kill them right before you roll and have the amalgamation tank run through the residue on the ground with the amalg right before you roll( have him gripped if possible to the stacking position ). As i said we havent tried it yet but I will try to provide you with feedback about this as soon as we try it. Until then - good luck with the boss, its really boring for real.