Magikarp. If you give it an exp. share, It will evolve into gyarodos. I have a golden magikarp right now(i have an action replay code for it. I am not that great,)
I go with feebass, bidoof, magikarp, metapod, pidgey, and ledian.
Magikarp <lvl 15, Silcoon, Cascoon, Metapod, Kakuna and Wurmple
Metapod evolves into Butterfree.
to catch a shiny metapod go to viridian forest and stay in the grass wait till you find metapod keep finding metapod until it glitters.
Metapod, but only if you catch it as a metapod.
Caterpie evolves into Metapod at level 7. Metapod evolves into Butterfree at level 10.
Metapod evolves at level 10 into Butterfree.
Metapod evolves into Butterfree at level 10.
Only Magikarp, get a better one for more variety
To get a metapod, you can either find a caterpie in the Viridian Forest and level it up to level 10 or you can look for a metapod in the Viridian Forest as well. Metapod is a little more rare than caterpie but if you are just determined to get metapod, it shouldn't take longer than a few minutes.
Metapod evolves into Butterfree at Level 10.
Yes, Caterpie evolves in Metapod at level 7