If you wanna talk about funny scenarios, maybe Chris "the Crappler" Leben will beat Chuck.
As for sylvia, he doesn't have the history to back up his skills. He hasn't really proven that he can beat someone with great striking. The fact that he didn't have the power to KO Assuerio Silva is just proof that he doesn't have as much power as he would need to take Chuck.
Sylvia has only beaten 1 figher with a win legitimized as "KO" (though he has 5 wins by TKO). Apart from Arlovski and Mir, his resume isn't that impressive. I don't think that Sylvia could take half of the fighters that Chuck's thrashed, and so I don't think that he take Chuck.
When I say half of the fighers Chuck has beaten there are really three that I'm sure he wouldn't dominate: Babalu, Randleman and Couture (in his prime). I think Sylvia would struggle with anyone who could take him down, like Monson.
If you really want to talk possibilities, do you really think that Sylvia would dominate Belfort and White like Chuck did? I don't.
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