The user can rapidly regenerate. In other words, they recreate lost or damaged tissues, organs and limbs, sometimes slowing, or even stopping aging. The rate and amount of healing vary widely; some can regrow missing limbs, others must put the limb back in place for rapid regeneration. The user is generally in very good physical shape, as their bodies are constantly reverting to a healthy state, granting them nigh-inexhaustible stamina and vitality. This regeneration process also increases the speed of processes the body uses in the healing such as endorphin production to mitigate pain reducing the amount of time and severity the subject feels discomfort leading to an increased pain threshold. Other processes included are the procution of adrenaline and the fight or flight response which are greatly extended by the increased recovery leading to increased physical performance as the subject gains elevated strength and energy while also able to push their bodies harder due to decreased sensation of pain.
It has several different levels that range in potency from what is essentially just faster natural healing to being able to regrow limbs or organs, or even a severed head.
Higher levels allow characters to regenerate from even more severe wounds, such as being blown to pieces, reduced to a single cell, vaporization, and even complete physical destruction and beyond.
Instances of characters being wounded and inexplicably recovering off screen should not be taken as evidence of regeneration unless supported by further context. This is due to reasons ranging from possibility of off-screen treatment to continuity errors.
Low: Merely an accelerated healing ability for normal wounds, allowing the character to heal wounds that would normally take days, weeks, or even months much more quickly, sometimes even in just seconds. For machines and vehicles, this would just be regenerating basic exterior damage.
Mid-Low: The ability to heal wounds that would normally leave large scars, such as severe burns or deep injuries. For machines and vehicles, this would be regenerating damage that would normally leave large dents and openings.
High-Low: The ability to regenerate severed fingers, toes, or ears, minor organ damage, and even potentially reattach lost limbs. For machines and vehicles, this would be regenerating some interior damage, along with some minor critically damaged or destroyed parts.
Low-Mid: The ability to regenerate lost limbs, and even from severe organ damage or destruction, including traditionally fatal wounds and disembowelment or horizontal bisection. For machines and vehicles, this would be regenerating minor parts and more extensive internal damage. From this point onwards, characters are considered to have achieved Type 3 Immortality.
Mid: The ability to regenerate from decapitation or severe brain damage. For machines and vehicles, this would be regenerating from the destruction of critical parts, such as the engine.
- Examples: The Dovahkiin (The Elder Scrolls), Shido Itsuka (Date A Live), Misogi Kumagawa (Medaka Box)
High-Mid: The ability to regenerate from being blown / cut to pieces, or from a small piece of the user's body, such as a severed head, a single organ, or a finger.
Low-High: The ability to regenerate from having no solid parts of the body remaining. This can range from a puddle or drop of blood to even a single cell. For robots and machines, this can also include regenerating from a liquid state.
Mid-High: The ability to regenerate from having all biology completely incinerated. This includes being reduced to ash, dust, smoke, vapor, or plasma.
High: The ability to regenerate from a few scattered or lone molecules, atoms, or sub-atomic particles.
- Examples: Kakine Teitoku (Toaru Majutsu no Index), Solaris (Sonic The Hedgehog), Kaguya Ōtsutsuki (Naruto)
Low-Godly: The ability to regenerate from the complete physical destruction of the user's body, instead restoring it from their disembodied consciousness, whether that be their soul, mind, or equivalents.
Mid-Godly: The ability to regenerate from the complete erasure of the body alongside a non-physical aspect of the user, such as their soul/mind.
High-Godly: The ability to regenerate after the erasure of the most fundamental aspect of a character's existence that relies beyond the body, soul and mind, such as their place in the narrative (plot erasure), their entire history (history erasure), or the underlying concept(s) or information needed for them to exist (conceptual/information erasure).