Can some please tell me the DC needed for a Will save when interacting with the Shadow Armament Oracle Revelation
"Shadow Armament (Su): You can create a quasi-real simple or martial masterwork weapon appropriate for your current size. You are considered proficient with this weapon. The first time you hit a creature with this weapon, that creature can attempt a Will save to disbelieve; failure means the weapon deals damage normally, while success means the creature takes only 1 point of damage from the weapon’s attacks. The weapon deals only 1 point of damage to objects. At 3rd level, and again at 11th level and 19th level, the weapon gains a cumulative +1 enhancement bonus. At 7th level, the weapon gains either the frost or keen weapon special ability, chosen when the weapon is created. These abilities don’t function against a target that succeeds at its Will save. At 15th level, the weapon deals minimum damage (as if it had rolled a 1 on each of its damage dice) against targets that succeed at their saves instead of 1 point of damage. You can use this ability for a number of minutes per day equal to your oracle level. This duration does not need to be consecutive, but it must be used in 1-minute increments. The weapon disappears after 1 round if it leaves your grasp."
10 + half oracle level + charisma.
Thank you