Molten Core
Lucifron - Magmadar - Gehennas - Garr - Geddon - Shazzrah - Golemagg - Sulfuron - Majordomo - Ragnaros
Garr
Garr is hard the first couple of times give the amount of adds but after a while shouldn't pose much of a problem
Garr Abilities
Everyone couple seconds Garr has an aura that will remove a buff from everyone near him.
This is also a Aura and goes off every couple seconds snaring everyone near him to 40% movement speed.
Garr at random points will detonate one of his guards dealing damage to everyone around it..
Strategy
Have the Main Tank pull garr up to the west side of the cavern next to the big rocks. Have 4 warlocks banish one of garr's guard each and have a voidwalker on him to tank. Have 4 off-tanks which will grab the other 4 guards and tank them.
Before pull (Click to Enlarge) After Pull (Click to Enlarge)
Kill the 4 add's that have a off-tank on them then focus fire on garr keeping the other 4 adds banished until garr dies. Every time you kill a add garr gets a bit more powerful so watch out for his big hits around 20% hp.
The Pull
Have the Main Tank run up and pull garr back to the designated spot in the cavern. Have all off-tanks and warlocks run up and grab their adds and proceed to DPS one add at a time until the 4 unbanished adds are dead.
Move all DPS over to Garr then and focus fire him down, when he goes down return to the other adds and kill them