>>55651913Take your starter, that's Fire, Water, or Grass right there.
In most games you can just take the Route 1 bird, that's Flying which covers Fighting and Bug. In gen 3 you could alternatively opt for Skarmory.
You probably want a Rock and/or Ground type. If the game has Rhyhorn, there you go.
Electric types are always fun. I generally use one, and none of the roles I listed above have that typing. Typically if the game gives me Eevee it gets the Thunderstone.
After that, you have two more slots for pretty much whatever. I'd personally find a Dark or Ghost mon (not really doable in Gen 2 ofc), and then a Fighting or Dragon mon. Either that or you can have one of the last 2 slots be an HM slave. Then again you could use them as a team member anyway. Bibarel/Furret STAB Strength ain't no slouch.
Basically, look to cover as many types offensively and defensively as you can. Try to have as few repeat types as is reasonably possible.