These are sorcerous projectiles that the Wizard hurls at their foe. The following applies to magic missiles:
The target must be an enemy unit.
The target must lie within the Wizard's forward arc.
The Wizard needs line of sight to their target.
The target must be within the spell's range.
Wizards cannot target spells at units engaged in close combat.
Wizards cannot cast magic missiles if they are engaged in close combat.
Magic missiles always hit their target automatically.