There was a GP in Lines of Action in Swiss and Arena system, will that also happen in other variants?

Best regards
FS-Schach

You will have to talk to the Mind Sports organisation about creation of events Swiss/Arena, perhaps in their discord channel.
Lines of action is a base game rather than a variant of a game (e.g. it's variant is Scrambled Eggs which only had a swiss). My understanding is that some of the abstract events that are popular are also run as an Arena (e.g. Shogi, Xiangqi, Lines of Action, Othello, International Draughts, some of the chess variants).

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