In WoW players don't collide with each other. Every player is really just a point and a facing. There's no collision detection with spell shots. Of you're withi

In WoW players don't collide with each other. Every player is really just a point and a facing. There's no collision detection with spell shots. Of you're within range and LOS, you can cast the spell. And once the spell is cast it doesn't collide with objects. Basically, WoW gets around it by vastly simplifying player interaction.