The user can defend against attacks without their will of defending, as in that it is automatic and without the users control. This defensive performance can be triggered just like Automatic Attack, but instead the user goes on defense, and that grants protection to whatever. If the automatic defense protects the user, if not anything else, then users can automatically gain counters, evasions, and even create shields on themselves for protection of strikes.
Because this power is automatic, it goes off whenever the user is attacked, whether or not the user wants it to.
Known Users
Accelerator (A Certain Magical Index)
Saiai Kinuhata (A Certain Magical Index)
Ichigo Kurosaki (Bleach)
Breach (Generator Rex)
Gaara (Naruto)
Logia Devil Fruit Eaters (One Piece)
Stand Users (JoJo's Bizarre Adventure)
Vash the Stampede (Trigun)
Moord Nag (Worm)
Elsword (Elsword)
Known Objects
Exile (Last Exile)
Nanites (Nano List)
Logia Type Devil Fruits (One Piece)
Gallery
Accelerator (A Certain Magical Index) has a vector field that automatically defends him.
Saiai Kinuhata (A Certain Magical Index) has been inserted with part of Accelerator's brain patterns, creating an automatic armor of compressed nitrogen.
Ichigo Kurosaki's (Bleach) Blut Vene activating automatically due to his Quincy heritage reacting to his danger.
Crocodile (One Piece) trained his powers to activate by reflex, turning himself into intangible sand automatically if attacked.
Portgas D. Ace (One Piece) trained his powers to activate by reflex, turning himself into intangible fire automatically if attacked.
Enel (One Piece) trained his powers to activate by reflex, turning himself into intangible electricity automatically if attacked.
Smoker (One Piece) trained his powers to activate by reflex, turning himself into intangible smoke automatically if attacked.
Aokiji/Kuzan (One Piece) trained his powers to activate by reflex, turning himself into intangible ice automatically if attacked.
Kizaru/Borsalino (One Piece) trained his powers to activate by reflex, turning himself into intangible light automatically if attacked.
Akainu/Sakazuki (One Piece) trained his powers to activate by reflex, turning himself into intangible magma automatically if attacked.
Vash the Stampede (Trigun) manifests an array of bladed feathers to automatically defend him.
Stands (JoJo's Bizarre Adventure) like Yoshikage Kira's Killer Queen can automatically protect their user from physical attacks.