KEEN SENSES VARIANT
Some half-elves in Faerûn have a racial trait in place of the Skill Versatility trait. If your DM allows it, your half-elf character can forgo Skill Versatility and instead take the elf trait Keen Senses.
KEEN SENSES
You have proficiency in the Perception skill.
SOURCES
Sword Coast Adventurer’s Guide
Image – https://1d4chan.org/wiki/Half-Elf