Since I have been working with my emerald most recently, naturally my strongest are on that game. I have the most all my lv. 100's, and other well trained pokes on it. What about you?
Emerald. I restarted everything else. I have only my Blaziken at Lv. 100 and he's pathetic. My lv. 50s are perfect in training and could easily wipe put Rayquazaor my Blaziken no sweat. LeafGreen is going fine while I defeat all gyms with only Charizard and I don't trade before the Elite Four.
in XD I have all the shadows and only three left to purify and I have about three perfect teams whos levels are hovering around the late 50's to early 70's.
in Emerald I have perfectly EV trained all the legendarys and a few other pokes and have 5 lvl 100s at the moment(and all the gold symbols)
Edit: Ive just realised that this should most likely be in the pokepolls section.
In Emerald I have my lvl. 60 Frontier Pokémon and my lvl. 100 Blaziken.
In XD I have my lvl. 100 Beasts.
In Colloseum I have my lvl. 100 Ho-oh, Mewtwo and Rayquaza.
Usually I have them on my Emerald file, because it's my most favorite. But currently they are on my FireRed, 'cause I've restarted my Emerald. As soon as I'm able to trade with firered I'll my strongest Pokes back on my Emerald
All my strongest ones are on my Silver version. They are all about level 80 or higher and that game is the most complete (Pokedex, etc) out of all the other ones I have.
Sapphire, with my level 100 team: Jupetta, Ariados, Noctus, Mirokaross, Frygon, and Nendoll. Ariados was raised to level 100 on Fire Red and then traded over, but the rest were trained right on Sapphire.