It's just a silly thing to do, and well, thiskindof challenge exists, wand was done with almost all types (if you count double types, and all variants of the same game, meaning Red, Blue, Yellow, Leaf Green and Ruby Red).
So it is very likely that practicaly all solo mon is viable in one way or another, INCLUDING magikarp (of a special release).
Here are the let's plays:
- normal type (rattata):
https://www.youtube.com/watch?v=mHdqpqy9VbU
- poison/flying (zubat):
https://www.youtube.com/watch?v=q_0WQaz7Jms
- rock/ground (onix) (FR):
https://www.youtube.com/watch?v=95IRkr7auuc
- psychic (abra):
https://www.youtube.com/watch?v=_R1oD6bau4g
- bug (weedle):
https://www.youtube.com/watch?v=HwC83pFtk60 (there's a paras run too somewhere)
- ghost/poison (ghastly):
https://www.youtube.com/watch?v=dWQMVm2agZc
- water (magikarp): this was actualy not done, but theorycrafted. The REGULAR magicarp can't win the game itself, but the UNIVERSITY magicarp in theory CAN. The difference is, UMK gets Dragon Rage on it. Only 20 legit ever existed, but with randomizers left-and-right obviously you can make your own.
Anyways, here is with squirtle:
https://www.youtube.com/watch?v=mx83SUgD9Rk
- electric (pikachu):
https://www.youtube.com/watch?v=x5i5p83PT5w
- fire (charmander):
https://www.youtube.com/watch?v=70Uq4Waa_k4
- grass/poison (bulbasaur):
https://www.youtube.com/watch?v=WDqKt1-Xwd8
+1: missingno:
https://www.youtube.com/watch?v=3mrmfb1mGWI
+2: ditto:
https://www.youtube.com/watch?v=TeWxEbl2kWQ
What this list lacks is 3 types:
- dragon (only dratini and its evos)
- ice (various)
- fighting
Strangely none did a fighting type. Dragon and Ice are in theory pretty strong, way stronger than the others, so my vote went on fighting. It likely can do anyway.
The selection for this is: mankey, machop (which can only max evo by tradin, so forget it), hitmonlee, hitmonchan.
Now what I want in a solo character in this game, is variety. And personaly I won't mind 100% hit chances.
Mankey/Primape is very limited, has only normal and fighting moves simply by existing, adding poison and electricity, maybe rock by TM. Not amusing.
Hitmonlee is generaly cosidered the better option over ...chan, but that's likely ina party. It can only do normal, fighting and by TM poison damage, and that sucks.
Hitmonchan on the other hand gets 3 elemental attacks. What I aftera while noticed only at lvl 30-40, but oh well. Doubles this problem, that its basic attacks only has 85% accuracy, and is one of those bullshit multiple attacks doing 2-5 hits randomly. But I can switch that to something else, so whatever.
Solo plays also have the problem of lack of PP (number of attacks can be done without resting), so gaining new abilities a lot later is again crappy news, but whatever. If allelse fails, there will be potions, though I'll try to not use any items during battle.
Oh, in case you wonder, there are special programs exclusively to switch the preset starters to something of your liking, so no problem there.
Now the first thing was to start the game. No problem, you don't have the type-disadvantage, so you win against the Rival.
Then the Rival appears again, that's better left for a bit later, as he'll have abit of levels under him, and we don't pick up reinforcements. But he's a pushover after Brock.
Brock needsa bit of grinding, but at clvl 16-17 can be done (if the random is not against you too much), just get rid of the Agility PPs,so when you run out of the punches you asap can start strougle. For some weird reason against geodude I constantly missed punches, but against onix I did reliably 4-5 hits per PP, and the onix missed me with bind almost all the time.
Note: grind in the forest, that gives the highest possible level ofenemies, and many can't even hurt back, not that it'd count.
On Road 3 catch a Spearow. Why? Because we'll need HM-slaves, and I'll want only 2 of them: Farfetched and Slowpoke. FF can be traded for a Spearow, and can learn Fly and Cut. SP can learn Surf, Flash and Strength. Heck, it can even do Dig if needed! Perfect.
Oh, all legendaries will be beaten for exp of course.
During the tunnel you'll get Mega Punch TM. Use it up for more (andmore efficient) PPs.
Hmpf. Forgot you have to catch 10 mon for one of the HMs (flash). We'll see, but sure you can find 2 Great Ball as "
hidden item". One of them is actualynot that hidden, as an NPC hints you on it, so that's more of a puzzle/miniquest-reward one.
And there's a regular ball as visible item.
And of course the starter comeswith its own ball.
And that's it. You have to buy the rest one way or another (thinking on the Safari Zone). I dunno when Flash comes to theplay for the moment...