The closest matches on Steam are Counter-Strike: Source, Splitgate: Arena Warfare, Insurgency, Call of Duty: Modern Warfare 2 (2009) and BattleBit Remastered.
From the Steam games with at least 2,000 reviews and 80% or more positive, we keep the ones whose main player tags match Tom Clancy's Rainbow Six Siege's most closely, then show the closest first.
