Anyone can enter. But I recommend not playing them unless u are looking for a total donkfest. In my opinion it's simply not worth it. I would recommend playing private freerolls or doing carbons fun steps.
you can play for hours and not get anything for playing that long. you are playing for the top 30 payouts and the average number of players is over 3000. so you are trying to get in the top .01% just to get paid 30 cents at the least and that is playing for like a few hours. its not worth it. dont waste your time. its a complete donkament. you'd be better playing the freerolls at juicystakes or somewhere else.
The structure of these aren't that great but they are free so only play if you have nothing else to do. I won 1st a few weeks back with around 4800 players but as others have said they are a donkfest and you have to get really lucky. Every other one I played I keep finishing around 150-200. And yes they are free to enter for anyone.
They used to have a great $100 freeroll on Sundays called "World Series of Tavern Poker".
500 runners usually. But checked today and looks like its gone..........
If you are lookin to get into some of the private freerolls on carbon sen me a PM, I can help you out and introduce you to the site that host some of them.