Blade Field

The user becomes unable to be hit by any un-magical weapon, as the user projects a force field like area five feet around their body. Any magical weapon must make a d20 strength check, and on a fail (10 or lower) they bounce off. If they succeed, they hit for their damage

At higher levels: When you use this spell with a fifth level spell slot or higher, the check goes up by one (to a max of 15)