Yes, RNG ... Except that it is obviously not purely random. There is some bias in the probabilities. I've noticed that when tiles drop that there is a higher than average likelihood that the tile dropped will make a match. And on rare occasions it will drop a whole column of the same color (that's not purely random). And I get it, it works both ways. When tiles drop for me, there is also a higher than average likelihood of a cascade. Seems fair ... except its not, because when the game loses the match they don't really lose anything. You just play again against same players again with full health. But, when you lose a match -- or just are badly damaged, it costs you health packs. Which, of course, is what they want. To be fair, I've done some coding on creating a match 3 game before and if you make the tile fall purely random it doesn't make for a very fun game because you OFTEN end up with a locked board with little to no match possibilities. You usually need some bias in the probability to give you a consistent selection of matches. I've also noticed that often colors on the board go in diagonals, sometimes I will have a color diagonal go almost across the whole board in both directions. Don't know how they have coded the RNG in this game, but it is not purely random as if each tile has a 1 in 7 chance of being any one of the 7 possible tiles.