SimOrg is an online Yu-Gi-Oh! dueling simulator designed for players who want to play and practice directly in a web browser. The platform offers free access to manual duels, with account creation and login available for users who want to participate. Its duel board includes the game’s zones, pendulum scales, and extra monster zones, supporting the layout needed for competitive play.

Players can build and save decks using the integrated deck builder, and import or export deck lists in YDK file format. Side decks are supported for match play. SimOrg also provides rating-based matchmaking, including ranked single duels and best-of-three matches, so users can challenge opponents and progress on a rating ladder. Beyond playing, members can spectate games and share replays through a URL, making it possible to follow duels or revisit matches. With deck management, competitive matchmaking, spectating, and replay sharing gathered in one browser-based service, SimOrg serves as a practical online venue for Yu-Gi-Oh! players.