Rune

Runes are demonic sigils in Doom (2016) which upgrade the Doom marine's intrinsic abilities. There are twelve distinct runes, each of which must be earned by finding its rune stone, a green glowing monolith bearing the runic mark, and defeating the ensuing rune trial, typically a battle which occurs in a small enclosed space disconnected from other game play areas. The runes are permanent upgrades, but only a certain number can be equipped at a given time, based on the Praetor suit's current capabilities. A maximum of three runes can be equipped when the protagonist is at full power.