Double-up (sometimes it is called “gamble”, "risk" or the other names with a similar meaning) feature does not affect RTP (Return to Player %) or House edge of online casino slot. Hence, it is pretty much neutral in terms of increasing or decreasing your winning chances.
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However, the double-up could significantly increase the volatility level of such an online slot.
Further, I will try to elaborate on both statements alongside with other specifics of this feature.
In this article:
The double-up feature could be called differently depending on a particular online slot producer. You could come across other names such as “gamble”, “risk” and others.
It does not matter how they call it; everything comes down to these characteristics which distinguish the double-up feature:
it can be used only after you have hit some winning in online slot
the limited number of possible outcomes. You either double-up (quadruple-up in some cases) or lose
Whenever you hit any winning at online slot with the double-up feature, it makes you decide whether you want to collect the winning and continue to play in casual mode or to risk in order to double (or quadruple) the winning.
If you are lucky enough and manage to double the winning then the online slot gives you the same choice again. At this point, you can collect doubled winning or risk again, and so on.
I would like to mention that some online slots allow to double-up only winnings derived from pay-lines, but some of them let you do so with Bonus game and Free spins winnings as well.
The double-up feature is designed only in addition to main features. So, I guess, it would be unfair to expect it to be super fascinating at any extent. So to speak, options of the player are limited to these: