I am GM:ing my first campaign and I have one player in our group that's a power gamer and a diva in play. The power-gamer part of him I can handle, it's no problem but it's the diva part, that's driving me nuts.
For example, he wants to talk all the time and wants to interrupt me and thus guiding the game toward his liking(and overriding me).
I gave him a strict warning, that he can't hog all the attention, all the time. He took this in a way that; "Ok I get it. From now on, I have to raise my hand to get an opening". So, now he's waving his hand all the time and starts knocking the table or making weird noises, if I don't let him speak. Most of his talk is usually something describing his character, the accent he speaks, little details in his character's clothing, the intellectual superiority his character manifests etc. That b******t doesn't even help the group to forward in game. And he's very stubborn. Annoys me quite a bit.
Later I found out that he cheated in ability scores. According to him it was an accident and he will correct it. I can buy that. But then I found out that he build his character using forbidden rules. We have a house rule that forbids psionic and unchained rules. He obviously did unchained rogue for his second level(he is aiming wiz/rog/at build) to minmax character.
I'm considering some kind of punishment for his actions. But I've decided not to take the position GM vs PC's. I don't want to be that kind of GM. Also, means to "lower his steams".
Any advice would be appreciated.