Feat: Orbiting Runestone

You create a runestone that floats around you, and you Trace a Rune with a damaging invocation on it even if the rune could not normally be applied to an object. The runestone has 10 Hit Points. Each time a creature successfully Strikes you, attempt a DC 11 Flat. On a success, the runestone blocks the attack, so the attack first damages the runestone and then applies any remaining damage to you. If this damage reduces the runestone to 0 Hit Points, it explodes outward toward the attacker. If the attacker is within 15 feet, the rune etched upon the runestone invokes automatically, applying its invocation effect to the attacker. The attacker is the only one affected by the invocation, even if the rune could normally affect multiple creatures.

The runestone's magic is capable of maintaining the traced rune for up to 1 minute as it floats around you, at which point the rune fades and the runestone shatters. You can maintain only a single orbiting rune at any given time. If you try to create a second, the first one shatters.