If you are looking for an alternative and more engaging way of earning Bitcoins by playing games, then you might want to check out the fishing game Captain Pearl. When you join the game you get a free boat that will start catching fish for you, you also get 49 caught fish at the start and 10 white pearls in your balance. The Happy Berth Day fishing boat that you start with will bring you 7 new fish every hour (1000 fish = 5 Blue and 5 White Pearls) and you can exchange the caught fish for Blue Pearls (can be cashed for Bitcoin) or White Pearls that can be used to buy more fishing boats. Currently the exchange rate for 100 White pearls is 104060 satoshi or 0.00104060 BTC (1.0406 mBTC) and you can not only sell pearls, but also buy them to get a boost at the start by getting more fishing boats.
The game allows you to earn some more pearls playing various games or visiting ads, so there is no need to specifically spend coins to get them faster and of course your fishing boats will be catching fish that you can trade for pearls. There is a Pearl-A-Dice game that allows you to bet White Pearls on dice rolls, this is riskier as you may not only win, but also lose pearls. The Pearl-to-Click game gives you 0.5 or 1 White pearls for visiting websites of advertisers, you can win a few pearls absolutely risk free here, so do not miss the opportunity. There is also a Wheel of Fortune that you can spin to get some nice bonuses as well as a MasterMind game where you need to get a 4 digit secret number.
The game is fun and does not require you to invest anything to get started and build your fishing boats empire that will earn you real Bitcoins, so you might want to give it a try.