Immortality

Various forms of immortality have been theorized by the scientists of Helise but they all involve those who are immortal not dying when they would if they were mortal. They would recover from injuries inflicted upon them which would prove fatal to a mortal, or simply not be affected by them at all. In cases where the immortality would prevent death of old age, the aging process would also likely cease at the point when the immortality was acquired, or, if it's based on regeneration, aging would stop when the user's condition is on it's peak.

Immortals have an infinite life span, and can shrug off virtually any kind of physical damage. Some users are the defensive type, simply preventing such damage from appearing (invulnerability/protection), while others are the regenerative type, surviving and quickly recovering from anything you throw at them.