Kill order is often an important aspect of raiding and there is always much discussion about what to kill first in a pull. To that end, Blizzard implemented a serious of marks commonly and lovingly referred to as “lucky charms”. However, like all great and simple systems of management, there is much dissent over how they are used. This is a brief explanation of the marks and the best ways to use them.
Skull: Kill target. This will be the first mob killed in a pull.
X: 2nd kill target. This will be off-tanked until the skull is dead.
Square: 3rd kill target. This can be off-tanked or CC (crowd control) until a tank can get to it. Usually a hunter trap.
Star: Usually a sap, if available. In that case it will be an early kill target. Also used as a sheep or banish depending on the circumstances.
Moon: Usually a sheep. Often saved till last due to AoE nature of a mob or a whirlwind ability. Using a sheep can keep the mob permanently CC’d through the course of a pull.
Circle: This mark varies based on the raid make-up but will usually be a sheep or a banish depending. Again, a later kill target once the rest of the pull is dead.
Diamond: Again, a varied mark. Often used for a banish depending on the pull.
Triangle: Not to sound like a broken record, but also a varied mark. Sap, sheep, banish.
Through A Healer's Eyes 