>>48323297The obvious problem is that you're dumping lots and lots of experience into a single mon, so it's going to be levelling a lot and quickly. Ideally, you want a game that keeps up to a certain extent. HGSS is good, with the caveat that you're basically untouched for seven out of either kanto gyms, with Blue and Red being decent challenges. I did a Platinum run in a previous life and need to revisit it because it was obviously challenging enough that I'd cheated by having to use a revive at the end of the game. Emerald, despite the jump between Wallace and the post-game Steven battle, I'd consider an antithesis of a good solo run game.
To be honest, of all challenge runs, a solo run is probably the easiest of the lot. It's dependent on the typing of the mon you pick, but you end up levelling so much that it's too common to be able to steamroll everything.
