We have a lot of games here with a different number of prizes, but how do we know someone can get a win here and the prize is up? So that even late still has the possibility to join, and is there a certain time limit, deposit or limit in this event?
You can check any event by clicking on "Read more", there you can check the rules and requirements for every event. It's hard to win in these events, too many people play all over the world... Galactix Frozen Forge Christmas Event will be their exclusive event, so maybe we will have more chances to win something actually. By that time you can try the BTCGosu contest on Galactix https://bitcointalk.org/index.php?topic=5522490.0
When more providers & slots?
I believe that many more slots will appear very soon. While they don't appear, I'm testing the ones I've never played before. It's very interesting. I play with minimum amounts just to have fun and then I wait for the winnings. But I'm just testing and I haven't had any significant winnings yet. But I hope we have news soon!