My son is crazy about pokemon and I am crazy about my son.

He owns a Gameboy Ds Lite and can play DS and Advance games.

He has these games now:

Pokemon Sapphire-gameboy advance
Pokemon Leaf Green-gameboy advance

Pokemon MD Explorers of Sky- DS
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Now from my research Pokemon MD E Of Sky doesnt help him in collecting.

And the two advance games he has do but there may be a easier or newer version of these he can play to achieve same results.

He is not gonna start his journey until we get a list of the correct games. Like instead of sapphire isn't emerald a newer version with same pokemon? Idk just needa good answer.

So to make this simple can someone give me a exact list of the newest games in order that I would need to buy so he can TRY to collect every possible pokemon including legendaries. And ones he can't collect he will trade for or whatever.

I just want to know what games are needed now he needs to collect all pokemon he can collect.

I know that he will need to trade and breed and other things to get every,every pokemon. But my question is what is the least and newest games we need to buy to collect all we can before trading and what not.

Simple answer are awesome, just a list so I can buy or trade for those games and get rid of games we don't need.

He has not started playing any game other then Pokemon MD EX of SKY, so he will start fresh and with the oldest game on list first.

Thanks fans I really need this help.