According to Kyle, Chim was the name of the god that is dreaming the entirety of the Elder Scrolls universe, and if someone were to discover this fact, they would either disappear or get superpowers. However, it was later brought up by Chat that according to the series' lore, "CHIM" is the realization that one is inside the god's dream.
Chim was officially introduced into the lore of Easy Allies during the Bethesda E3 2017 Press Conference. It started when the Allies were discussing the possibility of Wolfenstein and Doom being connected, and whether a crossover could ever happen. When Starfield came into the conversation and Huber mentioned the rumors about it being connected to both Fallout and The Elder Scrolls, Kyle brought up his version of Chim in order to show just how possible it is for the games to be set in a shared universe. The Allies found this amusing, and after a brief period of laughter, returned to the serious discussions they were having prior. Chat, however, was not so willing to let go, and for the rest of the pre-show, and a large portion of the conference itself, they continued to talk about it, and even the Allies themselves made a few jokes throughout the show. Chim ended up becoming the mascot for the rest of E3 and a beloved character inside the community.
As the event came to a close, the Allies made the decision to lock Chim away in a vault and stated that he was not to be discussed or mentioned until the next E3. This proved to be true when, on June 8, 2018, E3 officially started for the Allies after the E3 2018 Betting Special, which portrayed a scared Kyle and Huber (with a special cameo of God of War director Cory Barlog) opening the unassuming vault and allowing Chim to rain terror upon the Allies and E3 once again.
The vault has been kept open since then, but the Allies have made no mentions of this, or Chim itself.