i see a lottery when i enter in site but how to earn a ticket?

You buy lottery tickets from here: http://forum.toribash.com/tori_lottery.php However, there are no lotteries running at the moment.
If you have any questions about the prices of lotteries, well that all depends on what the prize is.

when is the next one?

Whenever Crux makes a new one. He's currently away right now.

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