The RISK: Global Domination Community has organized itself on various Discord servers.
Here are some of the largest ones:

RISK - Unofficial Community Channel with 3000+ members:

Cadriel CCR - Risk, Chess, Rubik's Cube, smaller but very friendly community

Master RISK - RISK for streamers and viewers alike:

RISK 4 Ever - Playground of the champions. For those who want to play Grandmasters:

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