The Yiga Armor is an armor piece found in Tears of the Kingdom.
Tears of the Kingdom
"Armor supplied to members of the Yiga Clan. Defensive parts are minimized for silence, so it's lacking in protection."
Link receives the armor from Konba at the Akkala Ancient Tech Lab. As part of the Presenting: The Travel Medallion! quest, Link will travel to the tech lab, but will encounter a Yiga Footsoldier and a Yiga Blademaster outside. After defeating them, he'll meet Konba inside. After thanking Link for taking care of the Yiga Clan, he'll give Link the Yiga Armor.
There is also an Ascend platform directly under the Tech Lab in the Depths, and rising up through the floor of the Lab before visiting from the surface or getting the quest will startle the Yiga warriors inside. They will accuse Link of trying to sneak past them and challenge him to fight them outside. After Link defeats them, he can then go inside and rescue Konba to obtain the armor.
|★||3||2 x Octorok Eyeball
|★★||5||3 x Fire-Breath Lizalfos Tail
3 x Puffshroom
|★★★||7||5 x Ice-Breath Lizalfos Tail
5 x Keese Eyeball
|★★★★||12||5 x Electric Lizalfos Tail
3 x Black Hinox Horn
10 x Mighty Bananas