Dumb: Chucking lighted flares and other junk onto the field in the middle of a match.
Dumber: Taunting a player from another team with racist chants (This isn't exclusive to the Russians. The Spanish - who already have a lousy history when it comes to prejudicial behavior toward opponents - have also been at it in this tournament).
Dumbest: Staging a "march" to celebrate your independence in the capital city of a country you've historically used as a pinata, most recently repressing and using as a shield for almost 40 years, on the day your national team is supposed to face the national soccer team from said repressed country in the second most important soccer tournament in the world.