About Eric Rosen
Eric Rosen is an American International Master (IM) and chess educator best known to a global online audience as imrosen on YouTube and Twitch. Born in 1993 in Skokie, Illinois, he learned chess as a child, earned the FIDE Master title in 2014, and reached the International Master title in 2015. He competed for the Webster University Susan Polgar Institute team during a strong period in collegiate chess.
His online following grew out of a soft-spoken, encouraging stream style and a willingness to play offbeat openings well below his classical strength. He is strongly associated with the Stafford Gambit (1.e4 e5 2.Nf3 Nf6 3.Nxe5 Nc6), an attacking sideline he popularised through dozens of instructive games against unsuspecting online opponents, and with the London System, which forms the backbone of his everyday repertoire as White. His exclamation "Oh no!" — usually uttered when an opponent walks into a tactic — became a recognisable catchphrase within the chess-streaming community.
Rosen's teaching style favours slow, principle-driven explanations over rapid calculation. He frequently breaks down endgames, explains why certain moves are "natural", and reframes blunders as teachable moments. Improving players in the 1200-1800 rating range tend to find his content particularly approachable, and many of his most-viewed YouTube videos focus on themes — knight endings, opening traps, blitz time management — rather than top-level theoretical novelties.
How his Chessiverse bot plays
Eric's Chessiverse bot is calibrated to 2357 Elo, modelling his typical online speed-chess strength rather than his peak classical level. It favours the London System with White and the Petrov Defence with Black, gravitates toward calm middlegames, and converts simplified endings with characteristic patience. Players seeking sharp tactical chaos will find the bot less interested in complications than they might expect — which is exactly the point.