The Coliseum is a forum on the Total War Center. It's home for the non-categorized games and competitions such as the "How Famous are you on TWC?" or "The Catchphrase Game" as well as housing the Total Guess Competition main thread. It's universally known as good place to raise your post count without having to spam the Thema Devia or to be chased by Moderation as a wannabe spambot!
Don't forget to check the subfora, in particular the Interactive History one!