I'm playing around with how I want to introduce more run variance.
The screen is very bad and needs some gizmo in the middle showing what is actually happening, but before starting a run you can turn on modifiers that change some game rules. Although this won't be unlocked immediately so the player can see what normal is like, before they turn on six rules at once and activate clown mode.
Some of these just let the player character become more powerful or do a neutral change, so they're not strictly about making the game harder. Although, who knows, maybe something will happen if the player takes more hard modifiers than easy? (me, I know, something will happen).
Right now these are kind of boring. Yeah, it's nice to have a new spell and it's harder to start with less mana, but I've been experimenting with some bigger rule changes and striping out things like enemies having 10% more health. So shops can now take health as currency (I may have got carried away and made an alternate shopkeeper because I thought it was weird the current one started doing blood transfusions), or adding a time limit to the players turn (and not a nice PAD time limit, it just starts and it's awful and I kind of like it).