Ward

Blocking; Resisted by subject spell 
When cast immediately after a spell is thrown at its subject, this spell can prevent the opposed spell from working. It works against only a single magical attack. If an attacking spell affects several people, each Ward can only save one subject. It does not protect against missile spells. 
The caster may only Ward against a spell that he knows at skill 12 or higher; a caster who knows (for instance) Sleep may also ward a single subject against Mass Sleep. The caster rolls at the lower of his Ward skill or his skill in the spell being warded. The caster must announce he is using Ward before the opposed spell’s subject tries a resistance roll. If it turns out the spell being cast is not one the defending mage can ward against, the ward is wasted.

Cost: 2 to cast it on yourself, or 3 to cast on anyone you can see. You cannot Ward someone you cannot see. 
Prerequisite: Magery 1.