All casters have a certain amount of resistance to a Dispel attempt. Thus, to successfully dispel, the attacker must win a Dispel Check.

Attacker rolls:

• 1d20 + Caster level + casting stat (Int/Wis/Cha/etc) bonus

Defender's DC:

• 11 + Caster level + casting stat (Int/Wis/Cha/etc) bonus