Pariplay decided to do something unprecedented, and are donating 10% of all profits from this game to Save The Rhino International foundation, and the game serves to increase the awareness about this endangered species while at the same time it's offering a very popular wildlife theme. This is amazing, and I think the game should be played because of this alone. So I've played it for real money for several hours, and found that it's a quality slot game, perhaps even one of the better classic slots with an African wildlife theme. Main game and paytable The game is played on a six-reel board, with the first and last reel being three symbols high, whereas the central four-reel part is actually a 4x4 board on which 4x4 Mega Symbols can land. There are 100 paylines that pay left to right, and during the free spins there are 40 paylines. Mystery Mask symbol is a special African mask that conceals other symbols beneath it, which increases the fun just a bit. The paytable gradually progresses from a 60 coin prize to a 500 coin prize for six-of-a-kind, and four of the ten symbols in the game are card symbols. Prizes for five-of-a-kind are also generous, and anything below that can't really make you any money and will just keep you in the game for longer. The six high-win Animal symbols can appear as 4x4 Mega Symbols. Rhino is the Wild, and it can also appear as a 4x4 symbol. You can expect to win on roughly 20% of your spins. Bonus features The bonus game is triggered when you land one Bonus Scatter on reel 1 and another one on reel 6. You'll need to pick 3 matching symbols to win an instant prize, or you can get free spins with varying multipliers and features. The cash prize is 15x your total bet, and there are five free spins options you can win: 10 free spins with a x5 multiplier, 15 free spins with a x3 multiplier, 20 free spins with a x2 multiplier, or 50 free spins without a multiplier but if you land two Scatters the multiplier will increase by x1. There are also 7 Rumble Free Spins, where the base multiplier increases by x1 when you land two Scatters and all Wilds get locked for the remaining spins, and any Mystery Mask symbol grants you an additional free spin. All free spins games pay on 40 paylines, not 100. Rumble Rhino Slots RTP Rumble Rhino has a theoretical return to player (RTP) of 95.52%, which is decent for a classic slot game but not really in line with modern standards. However, since a portion of Pariplay's profits from this game goes to a good cause, you probably won't mind the RTP is a bit shorter than it could have been. This is still a game in which you can make money from many different directions, and it's a better choice than most similar slots. There are good classic slots with an African wildlife theme, and this is probably among the best ones. Conclusion Rumble Rhino is a quality slot game, and it will appeal the most to classic slot players, though everyone should play this slot. The free spins features can offer really good prizes, and so can the 4x4 symbols in the main game, and this is simply a slot game with few, if any, downsides. Everyone should at least try it out.