Catch them all

>>26959458
X,Y and ORAS have all the Pokémon barring event legends.

You just need to have those 4 games

>>26959458
Are you saying you haven't caught them all?

Should've specified, sorry. The plan is to play through each generation and catch all in said generation while doing so, then import to the next game up to alpha sapphire.

The gamecube games and that Ranger game with the manaphy.

disregarding gen 1/2 cartridges, you can get all of them via generation transfer. you will need a gen 5 game.

>>26959495
I have before, up to generation 5. At the time I only had white diamond and emerald. Any that I couldn't get myself I got from my cousin. My girlfriend at the time decided she wanted to play, erased my save. I left her because of that, and just to make it worse she stole my game when she left. I figured it was time to redo it, the right way.

>>26959458
You can get all of them in Gen 6 (apart from event legendaries, which you should be getting this year anyway)
For the few that are only in X or OR, get any gen 5 game so you can either catch them there or transfer from gen 4.

>>26959495
That only works if someone says that they haven't never caught them alll and possibly never will.