Playing blackjack is all well and good but if you want to increase your risk and potential reward, you've got to give 21+3 a go. This is a side bet which is available in most online blackjack games and serves to pay out one of 5 potential rewards. How it works is by using the first two cards you're dealt and the dealer's face up one. When combining the trio, you could potentially win massive. We're talking about a 100/1 payout. Find out more in the 21+3 Blackjack Side Bet Review below.