Firefly pendants are the 31 metal tags worn by members of the Fireflies, scattered through The Last of Us Part I's main story. Finding all of them unlocks the Look for the Light trophy.
The Quarantine Zone: 3 (Vigil, Glueck, Liu). The Outskirts: 4 (Lenz, Kiper, Davidson, Jiang). Bill's Town: 3 (Wang, Vincent, Mrozik). Pittsburgh: 3 (Risk, Reed, Rios). The Suburbs: 4 (Scheffler, Righetti, Fuentes, White). Tommy's Dam: 2 (B. Pino, Oliverio). The University: 5 (H. Pino, Rohner, Warren, Griggs, Hickman). Lakeside Resort: 3 (Riley, Kristof, Braun). Bus Depot: 3 (Perich, Nicole Hoo, Natalie Hoo). The Firefly Lab: 1 (Stewart-Seume).
Naughty Dog ran three fan contests for art, video and cosplay, and eight winners from each had their names engraved on pendants in the game.
B. Pino's Firefly Pendant
B. Pino's Firefly pendant sits on a desk in the Hidden Pines Corral ranch house, in the Ranch House section of Tommy's Dam. It belonged to Brent Pino.
Braun's Firefly Pendant
Braun's Firefly pendant rests on a bench inside a gazebo next to the first cabin at the resort, in The Hunt section of Lakeside Resort. It belonged to Paul D. Braun.
Davidson's Firefly Pendant
Davidson's Firefly pendant lies underwater in a stone rotunda in The Capitol Building section of The Outskirts. It belonged to Melinda Davidson and is easy to swim past.
Fuentes's Firefly Pendant
Fuentes's Firefly pendant is underwater next to a sunken car in the Sewers section of The Suburbs. It belonged to Eddie Fuentes, and you have to dive for it.