DatSheffy

DatSheffy shows Twitch staff member Sheffy wearing reflective blue sunglasses. Sheffy's own profile describes him as Twitch's Director of Network Engineering and jokes that he is the owner of "the best blue sunglasses in the world," matching the most conspicuous detail in the emote.

The command reads like `dat Sheffy`, turning his handle into a recognition reaction. A 2015 Dota 2 chat guide records the early joke directly: when viewers noticed Sheffy watching a stream, they would spam DatSheffy so the room filled with his own sunglasses-wearing face.

Viewers type DatSheffy in Twitch chat for Sheffy references, especially as a callback to the old practice of spotting him in a Dota stream and filling chat with his face. The blue sunglasses also make it a natural confident or deliberately cool reaction.