Chicago Cubs

How to spot a serious sports rivalry: Notice the local theme parks talking smack ahead of a playoff series.

That's a good barometer for measuring the animosity between the St. Louis Cardinals and Chicago Cubs. Ahead of their playoff matchup, Six Flags St. Louis fired the first shot, dissing the Cubs with a big sign at its entrance:

The Six Flags Great America in Illinois, meanwhile, wasn't happy to see the trash talk. Not content to settle for sass, Great America upped the ante by proposing a big bet on the National League Divisional Series.

As most of you know by know, the Cubs took the series in four games, sending their rivals packing -- and forcing Six Flags St. Louis to follow through.

Let this be a lesson: Gambling is dangerous. But when you lose, have the guts to pay up.

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