Slot machines in which you can double up your winnings much as you would do in video
poker were invented in Australia. Gamble
feature slots of this type spread rapidly to the rest of the world. Providers of software for online casinos quickly latched onto the idea of introducing similar games online. In Australia these machines are called "pokies".
An attractive advantage for players of these gamble feature slots
is that tthe odds against you are fixed. If you can choose from two options in a double-up game, for example, there's a 50 percent chance you'll win.
Only two slots currently offer a double-up option. Both are 5-reel video slots with 9
pay lines and a max bet of 45 coins (9 lines and five coins per line). If you hit the bonus round, there are 15 free games to be won and you can re-activate these games an unlimited number of times. The slots in question are Thunderstruck and Spring
Break, which can be played at the Microgaming online casinos advertised on this
site.
In Double Up Gamble Features you have to select different
combinations: Red / Black or Diamonds / Hearts / Clubs / Spades. You can play with denominations from 1 cent to $1. At stake is a maximum jackpot of 10,000 coins (and 30,000
coins in the free games).
To clarify, let's consider the Thunderstruck video
slot. Their top jackpot is 10,000 coins with a second highest prize of 2,000
coins. You're unlikely to hit either of the combinations required for these large payouts but you could grab some of the many smaller 50-coin and 100-coin prizes.
Suppose you won 100 coins and switched to the gamble screen. Here you might convert your 100 coins to 1,600 coins if you were to succeed twice in the bonus game. Staking this entire amount on a third gamble could net you 6,400 coins.
These type of games, in particular their double-up features, offer a captivating way to expand your winnings without the need to hit a big jackpot.
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