Superior Darkvision

^{Mistveil → Rules → Superior Darkvision}
Creatures with Superior Darkvision are able to see perfectly in any type of Darkness, including that created by deeper darkness.

Reasoning: Although underground natives like Dark Elves usually have twice the distance on their Darkvision, making it more unique and interesting than normal Darkvision that many races have seemed like a good way to differentiate them.