WHOOPS Endquote, I forgot to specify that the solos on my Charmander only apply to TRAINER OWNED versions of it. Well anyway, that's not going to fly anymore since the Geodude line is way to dangerous for you to battle with a Charmander line Pokemon in a Nuzlocke.
So, for this challange it's also going to be a Charmander, but this time the restrictions are reversed. Instead of soloing every explosion/self-destruct lined Pokemon, it's not allowed to fight ANY of the aforementioned lines. If it encounters them, it must switch out. It's terrified of it's own flames, and as such cannot have more than one Fire type move at a time, and can only use it when it has to, when its opponent is either weak to it or resists all your other moves (for instance, this means you can't use it against a normal type but a Grass type is AOK). It may never learn Blast Burn because that's way too scary for it. Have it Solo Erika to evolve into Charizard, because it wants something easy to make sure it doesn't die horribly.
Finally, name it "PTSD", as that's the reason why it's so terrified of all these things.
Enjoy! And someone please give him a Mankey or something so Brock is easier for him; I know from expeirence that Metal Claw alone is not enough.
EDIT: I'm reserving an Aerodactyl for KS' friend, to replace the Zubat line later on (he can have both challanges that way, sound cool?)
EDIT2: Alright KS, your friend gets "YourReward" the Aerodactyl. Having suffered through most of the game with the useless Zubat/Golbat line, he now gets to use one of the most badass Pokemon from the first generation, and he gets to do so with minimal restrictions. The only restrictions are that it must have a moveset that consists of all different attacking types ASAP, and that it must have both a Flying and Rock STAB ASAP. I wish your friend luck!