Mechanic: Modulo Dice odds tempering
A quick concept: Reading dice in different base numeric systems yields different odds in a simple way.
1d6 mod 4 = 1,2,3,4,1,2. 1 & 2 each have a 1/3 chance of being rolled while 3&4 each have 1/6.
1d6 mod 2 = 1,2,1,2,1,2, basically evens/odds 50% split.
2d6 mod 4 = ....
Reading the results of dice in a different mod is very easy, but estimating the odds is extremely complex.
This creates a system where the odds favor lower values (1,2), but players will struggle with solving the gamble.
Allowing players to adjust the mod of a gamble as a game mechanic allows for a push-your-luck system where players have more granular control over the luck factor, while still keeping the future opaque.