Raid Tank Group Setup: The raid tank group is the most important group to put together well. If it's not, no matter the number of nukers you have Rose Zulie, you're all going to die.

My personal favorite setup is a tank, two Bishops, two Shillien Elders, two Elven Elders, a Sword singer, and a Warcryer. With this setup, you have plenty of MP regen for the Bishops (your main healer) and rechargers for the tank. Plus, you have two people with a 30% heal, and now in Chronicle 4, Balance Life.

When the raid boss does 300-1000 damage a hit to a tank AFTER the shield block (damage depending on your level and level of the boss, of course) several 30% heals are very important.

Alternatively, you could swap out one of the rechargers for a Blade dancer for Dance of Concentration.

Alternatively, swap out one of the healers for another tank. At the very bare minimum, I would recommend two Bishops and two rechargers on the healer side.

A Sword singer is NOT optional: Song of Earth, Warding, and (at higher levels) Vitality are a must. Because the 30% heal is so important for raids, having a tank with the most HP is usually more useful than one with a slightly better armor set.