Immunity

Immunity is a being's resilience or total impervious nature to supernatural powers, objects, effects, or forces that affect other members of its species. It appears that a creature's age, power level, and/or rank within its species hierarchy dictates if it is immune to its species' weaknesses and to what degree it is immune.

Characters with Immunity

 * Sam Winchester - He is completely immune to Croatoan Virus and demonic photokinesis. Sam is initially susceptible to Lilith's powers, but drinking demon blood he gained completely immunity.
 * Dean Winchester - He is completely immune to being made a Rabid due to the influence of the Darkness. While imbued with the power of the Mark of Cain, he became completely immune to Gaelic Obliteration Spell. Dean is initially susceptible to Abaddon's powers, but holding The First Blade he gained completely immunity.
 * Angels
 * Castiel (formerly) - While imbued with the power of the 30-40 million souls of Purgatory, he became completely immune to angel blades and angel wards.
 * Metatron (formerly) - While imbued with the power of the Angel Tablet, he became completely immune to angel blades and holy fire.
 * Archangels - Lucifer is completely immune to Metatron's spell and angel blades. He has limited immunity to The Colt. Michael, Raphael and Gabriel also have some degree of immunity to these angelic weaknesses.
 * Nephilim - Jack is completely immune to angel blades and angel banishing sigils despite possessing angelic heritage.
 * Demons
 * Princes of Hell - Azazel, Ramiel, Dagon and Asmodeus are completely immune to salt, holy water, devil's trap bullets, demon-killing knife, angel blades, smiting used by an average angel, and hallowed ground.
 * White-eyed Demons - Alastair is completely immune to iron, smiting used by an average angel and to hallowed ground. He has limited immunity to the demon-killing knife and holy water. Lilith is immune to hallowed ground. She also have some degree of immunity to iron, smiting used by a average angel, demon-killing knife and holy water like Alastair.
 * Multicolor-Eyed Demons - Samhain is completely immune to iron. He also had some degree of immunity to demon-killing knife.
 * Knights of Hell - Abaddon is completely immune to exorcism used by a men of letters and hallowed ground. She has limited immunity to demon-killing knife. Cain is completely immune to demon-killing knife and has limited immunity to devil's trap.
 * Crossroad Demons - Crowley is completely immune to hallowed ground.
 * Black-Eyed Demons - Astaroth may have been immune to iron. Father Gil, Meg and Ruby are completely immune to hallowed ground.
 * Ghosts
 * Jacob Karns - He is completely immune to hallowed ground and has limited immunity to salt.
 * Isabella - She has Immunity to hallowed ground.
 * Hugo Moriarty - He has limited immunity to iron.
 * Leviathans
 * Dick Roman - He has limited immunity to Borax.
 * Edgar - He has limited immunity to Borax.
 * Monsters
 * Alpha Shapeshifter - He is completely immune to silver.
 * Alpha Vampire - He has some degree of immunity to dead man's blood.