TriHard

TriHard comes from a picture of the streamer TriHex (Mychal Ramon Jefferson), who became known for speedrunning games like Yoshi's Island. The photo that became the TriHard emote was taken at a gaming event in 2012, where TriHex was making an enthusiastic expression after spotting something exciting. He later submitted the image to Twitch, and it quickly became an official emote.