Comment by yunusabd

If you find the base game too easy, I can recommend the IronMON challenge: You can only use one mon, permadeath, stats are randomized, all trainer levels are buffed by 1.5x and you can't level up on wilds. Along with numerous other rules to make it harder. There are variants that are borderline impossible to beat, like Super Kaizo IronMON. Out of hundreds of thousands of attempts, it has only been beaten once. Would make for an interesting optimization problem.

https://github.com/PyroMikeGit/SuperKaizoIronMON