The first casino where you can try to win something is http://www.zodiaccasino.com.
All you have to do is registering and than they will send you an e-mail with the name of the slots where you have 50 free spins. I made 90 credits and withdraw in the casino where i just needed to roll over the bonus but i did this using roulette, american roulette but you can alsaw play wherever you want to meet the wagering requirements for the bonus and than if you stilll have money you have to deposit the minimum amount trough the method you want to withdraw and than withdraw all the money.
Here are the indications and conditions from their site for this promotion:

How to begin your 50 free spins on Starscape Video Slot.

Ready to get started? It's really easy but here are some helpful hints to guide you through it.
To claim this promotion you will need the casino software. Download, install and register as a real player.
Once you have registered you will receive an email within 1 hour telling you that your free spins are waiting for you to claim.
Login to the software and open the Starscape Video Slot. Your 50 free spins will be ready for you to start.
No purchase is required to start your free spins.
Your 50 free spins are only valid for 7 days from the date of registration so make sure you use them all in this time frame.
If you get disconnected you will need to log back in to continue your free spins.
Any winnings will be paid straight into your Casino Bonus Account and can be played at your leisure on any of the casino games.
In order to withdraw any winnings accrued as a result of this promotion, you will be required to purchase any amount at the Casino.
You will also be eligible for $40 free if your first purchase is to the value of $100 or more.

Terms and Conditions
Play for free, win for real promotion.


Players must open a first time REAL account at Zodiac Casino during the promotion time period in order to be eligible for this promotion.
For the purpose of this promotion, players will be allocated 50 free spins. This amount cannot be increased or reallocated during the promotion.
Each spin on Starscape will be to the value of $0.25.
The 50 Free spins are for the purposes of this promotion only and can not be used as part of normal play.
Winnings will be transferred straight to the player's bonus account after which normal play through requirements will apply.
A purchase will be required at the casino in order to withdraw winnings acquired as a direct result of this promotion.
The promotion will be valid for 7 days from the date of registration after which time the offer will be null and void.
In the interest of avoiding any confusion relating to this promotion and the winnings transferred to the bonus account, please be certain to read the following wagering obligations:
Bonus amounts credited to a Player's bonus account are subject to 30 times play through before they may be cashed in.
Different games played may contribute a different percentage of the play through - up to 100%, towards the required play-through.
The contributing percentages are as follows:
Slots, American Roulette and Parlor Games count 100% towards wagering requirements
Table Poker, all Roulettes excluding American Roulette, Casino War and Sic Bo count 50% towards wagering requirements
Video Poker, all Blackjacks except Classic Blackjack, Craps and Baccarat count 10% towards wagering requirements
Classic Blackjack counts 2% towards wagering requirements
The wagering requirements (for withdrawal purposes) will start being counted from the time the free spins are finished.
Players who claim their winnings as part of this promotion will still be able to claim the Welcome Bonus of $40 free when they make their first purchase of $100 or more.
Players who have redeemed this promotion or the 1 Hour Free promotion at a Casino Rewards partner casino, will be required to make a deposit at a partner casino before participating a second time.
All promotions can only be claimed once per person, household, family, household address, email address, credit card number, or shared computer environment such as a library, workplace, fraternity, university or school.

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