[Arkham]

I was thinking of some sort of mechanic where you roll a combat die and try to predict the result. Essentially a gamble with odds that you're betting on. Before rolling, you have to say if it will be a skull, shield, or blank. The less likely the result, the bigger the gain. However, it's not just a matter of the result, it's got to be guessed right or you pay the penalty.

If not that, just make it a roll where the skull is bad, and the shield is decent, and blank is a big bonus.

Not sure. One of those type of approaches can put the player in Ash's shoes, leaving room for arrogance and confidence being called into question. Do you bet big, small, or not at all in fear of the possible outcome. You can turn it around or screw it all up worse than it was.