Front-facing

A limitation of most attacks or spells that the target must be considered "in front" of the attacker to initiate the attack or spell.

If you are not front-facing your target for those attacks or spells that require it, you will get the warning: "Target needs to be in front of you" and your attack or spell will not initiate.

Players can only dodge or parry attacks when front-facing the attacker. Mobs can dodge but not parry attacks from behind.

For ground-targeted area of effect spells, front-facing generally does not apply; for example, Blizzard, Blast Wave and Flamestrike can target an area behind the caster's back. As well, two units that are less than half a yard apart, measured from center to center, are always considered to be facing each other.