How to hate is important. For single bosses, single target hate will keep the boss on you. However, bosses with minions behave like group mobs: hating the minions attracts the leader, and attacking the elsword ed leader attracts the minions.Starting with a single hate and an AoE hate will pull the mobs to you, and then keep them on you. AoE hating builds a little more hate overall while the raid boss minions are around, but consumes much more mana over time.
Conserve your AoE hates, and experiment with your timing. Make sure that if there are ranged minions, they stay in your hate radius. Nothing causes more trouble than a rogue archer minion that decides the squishies are more fun to attack than you.Buffing should be done in unison. Many high level alliances do this anyway, but it's extremely important for raids. Each party should rebuff right before the raid starts.That way, one party doesn't start loosing buffs mid-fight, and reduce the raid overall damage output for too long--the time it takes a Prophet to rebuff a party can take about the same time a raid needs to kill a boss!