The Tiefling is a famously popular race in Dungeons and Dragons and is equally popular among Baldur’s Gate 3 players. Typically, they appear as humanoid creatures with horns and devilish skin colors ranging between red, orange, blue, and purple. Many Tieflings also have horns, scaley skin, glowing eyes with dark scleras, and many other unnatural features. They also have resistance to Fire and Dark Vision no matter their subclass.

https://screenrant.com/baldurs-gate-3-tiefling-subraces-explained/