From AmtWiki

The target of a Magic or Ability must be in range at the completion of an Incantation. The target being out of range at any other point does not prevent or interrupt the casting attempt. If a piece of equipment is the target, the physical equipment itself it what needs to be in range. If the incantation is completed and the target is not in range, the Magic or Ability has no effect but is still expended. For Magics and Abilities used at a range of Touch, any physical contact between caster and target is sufficient. Unless otherwise noted, Magics and Abilities with a listed range of Touch or greater can be cast at range Self. Magic or Abilities used at a range of Touch may only be used on players that are willing, Dead, Frozen, Stunned, or otherwise unable to move and unable to engage in combat.

Possible ranges are:
Touch: Others
Ball (Target must be struck by a Magic Ball)