The shield of Determination is a shield Determination souls use as a way to defend themselves from attacks. It appears the be red glowing circular shield, a crescent-like barrier, or just an invisible barrier around the user's body.
- Circular Shield: The circular shield makes its appearance in Do or Die. It's sturdy and is able to block most of Bete's Weapons, but can crack upon impact.
- Crescent Shield: This shield is able to block slash attacks. It was previously used to block a "car" that was about to hit Bete.
- Armor of The Red: This is an invisible barrier that surrounds the user's body to possibly reduce damage. Frisk can be seen using this in Love Part 2.
- Spherical Shield: This shield functions like the green artifact Alphys used. It can surround a target with a sphere causing the target to be trapped inside of it, though the target can still crack the sphere, it's unknown if the target can fully escape.
- Frisk didn't know how to spawn a sword or a shield in Season 1 because they relied on physical weapons that throws magic out of them, and didn't know how to make a magical one until Your Best Friend.
- Armor of the Red is something that is exclusive to Determination users.