Before your first spin on the reels
Scatter symbols land on the reels and can open the free spins, but how often that happens is not known in advance. Every spin is random, so the result of one session cannot be predicted, whatever the RTP version of the game. A quiet session and a generous one can both start with the same bet.
Each spin on the reels follows one of three RTP versions. The game rules show which version this lobby runs, so check them before the first spin. The version sets the long-run return, and the rules are the only place where that choice is written down.
Symbols line up across the paylines, and the biggest payout can reach x25,000 your bet, the ceiling of Big Bass Splash 1000. That ceiling is reached very rarely, and no session can be planned around it. Reaching it is possible but never promised, so keep the maximum win in view without counting on it.