A Guide to Horde Raid Groups
This guide has been created to help raid-leaders form the most DPS efficient groups for raiding purposes. Contrary to popular belief, every group with a warrior does not need a priest, and hybrid classes can contribute to raids even if they aren’t healing-specced. The following is a guideline to help with organization of groups within a raid that will give your DPS classes the best boost to stats.

General Raiding

To begin, let’s take a look at a basic 20-40 man raid, and the "important" classes to watch for:

Warlocks: Keep one with the main tanks, and make sure the off-tanks have one as well. Ideally, you should have at least one or two warlocks in your raid that are not specced for Demonic Sacrifice. The main-tank group typically consists of two warriors, a warlock with improved imp, a shaman, and a hunter. More on the other classes later.

Shaman: Try to keep Enhancement/Elemental shaman with your DPS groups, and Restoration shaman with your healers. A mana-tide shaman with priests is always a good idea, for when mana gets low for healers. A quick mana-tide will give a group full of priests just enough to get through some longer, tougher fights. Pre-BC, mages and warlocks don't really benefit as much, with the exception of mana stream/tide and a Tranquil Air for DPS-heavy warlocks. In DPS groups, let the shammy figure out if they need more Grace of Air (GoA) or Windfury (WF), and Strength of Earth (SoE) is usually a good choice. When putting shaman groups together, find out which rogues prefer GoA and put them in groups with hunters. Some prefer WF, and they can be grouped with a shaman and warriors.

Hunters: Typically, it’s helpful to have a hunter in the main-tank group, so the tanks know when the next pull is coming. Hunters also benefit from the +AP of feral druids, the True-Shot aura helps other DPS classes, and pairing them with rogues in shaman groups tends to be ideal so that the most may benefit from GoA.

Warriors: If they aren't main-tanks, they can be useful in groups with rogues and feral druids for their Battle Shout buff. It helps to make sure they have warlock imps in their groups as well, for the stamina buff.

Druids: Moonkin Druids are a favorite of caster groups. Four mages and a moonkin makes mages very happy, with the 3% crit increase. If you have a lot of moonkin, you can give one to the healers as well but typically mages and warlocks will get the most from the aura. Feral druids with Leader of the Pack give a great buff to DPS classes.

An ideal DPS-boost group would look something like:
Feral druid – Leader of the Pack
Hunter – True Shot
Shaman – GoA/SoE
Warrior – Battle Shout
Rogue – No buffs to contribute, but watch the crits fly!

As a healer, I tend to keep the main tanks in Group 1, just to keep things consistent. Everyone’s preference will be different when it comes to placing groups, and this is typically dependent on the individual’s UI.

Mixing and matching when necessary is ok when it makes sense, but for example, putting priests in warrior groups is usually unnecessary. Some folks prefer it for ease of healing, but in most cases, healers shouldn’t need their party interface showing when they raid. Hide the party view and just look at the entire raid.


Onyxia

Setup for this raid takes a little more finesse. All rules above apply, but certain considerations must be made. Make sure there are healers on both sides of the room. If odd groups go one way and evens go another, make sure there are healers in odd AND even groups. Also, you'll want two "whelp groups" - one even and one odd, if that’s the way you split. Mages on both sides for frost novas, and split warlocks appropriately. Also, be sure there is a shaman or two in the main tank group, for Fire Resist and Tremor totems in Phase 3.

I originally wrote this guide because my fellow raid-leaders tend to hand me raid leadership to organize groups, and I felt they could benefit from an outline like this. After a few pick-up ZG/AQ20 runs, I realized that it wasn’t just my guildmates that were sometimes confused about group-building in raids.

Also, it highlights the benefits of having hybrid classes of various specs. Enhancement shaman might not make great healers, but ask a warrior if he’d like an Improved Windfury totem, and see if a hunter says no to +88 agility from a buffed GoA. Ask a mage how they feel about +3% crit from a balance druid. The most hardcore groups will always tell you that the only good raid spec for a healing class is Restoration. I enjoy having healers that can buff DPS.

In general, keeping in mind group buffs as opposed to raid buffs will help sort out where people can be best placed. And if someone looks out of place, there's ALWAYS something you can do to make a group with a purpose. Good luck, raid leaders.