Disrespect
The other spell, called Infinite Life, consisted of a delicate process of cellular change gradually induced by mana, allowing cells to live longer and develop a special organelle capable of prolonging a person's life. This resulted in about a 25% increase in life expectancy in people up to the third kingdom.
Above that level, it had not yet been tested. Furthermore, the user would be immune to diseases related to cellular health, such as cancer, which even in high-realm mages could still manifest. It wasn't a spell that required advanced knowledge; the only requirements were tolerance to pain and the discipline to dedicate five hours a week to its development, a minimum amount of time compared to the benefit the person would receive.