Deleted

you could use sgtools and apply custom filters, easier to get rid of rule-breakers. you can fine-tune the ratio or cv required to enter :3

The best way to avoid having to reroll is to spread out the giveaways. You don't really need to check for duplicate winners, though. If someone wins a 2nd copy, they should contact you for the reroll, which will cut down on the amount of work you need to do.

There aren't that many people with level 8-10, so if you make multiple copy giveaways for a short timeframe, chances aren't too bad, that someone wins multiple copies, if he/she joined all of the giveaways.

I think a good idea could be to let the giveaways run for a longer time, like multiple days, but let them end at different days, so users could withdraw their entries, when they won something. They couldn't do that if all of these end at the same time!

Besides: seems that I was wrong about the need to delete your gieaways. Hum.. well, again, sorry about that

If you want to avoid rerolls - I think would be better not to run many giveaways at once, run one but with many copies. And make a day or two delay before next giveaway. This would minimize the risk that someone would win two giveaways of same game unintentionally.

Try to check how much is giveaways of game that you want to give already up. If not so much, then there is lower chance to rerolling