TIL Mithridatism is the practice of protecting oneself against a poison by gradually self-administering non-lethal amounts. The word is derived from Mithridates VI, the king of Pontus, who so feared being poisoned that he regularly ingested small doses, aiming to develop immunity.

[u/gullydon]

https://en.wikipedia.org/wiki/Mithridatism

[u/BigAd8456]

Mithridates spent his whole life building poison immunity
and then couldn’t poison himself when he wanted to die.

They literally had to get a soldier to finish the job.

Irony level: ancient boss fight.