Six Magikarp at level 5 a piece!
There is no best team unless you hack it. any pokemon can be good if trained correctly
my team
The best Pokemon team in diamond is piplup, shinx, starly, machop, budew, and cranidos
Well my team was Wigglytuff charizard
charmander
If you mean Pokemon Ruby, Sapphire or Emeraldm, they can be traded with a hunter on an island halfway between Lilycove City and Mossdeep City. Pokemon Platinum shards are used to tutor moves to Pokemon on Route 212, Snowpoint City, and the Survival Area.
By Strategy, if you mean best team of Pokemon, i recommend a solid team with a Dark,Psychic,Dragon,Water,Fire, and a Fighting Pokemon.
My team name is simple "Team Pokemon" because I plan to recruit all the Pokemon I can.
There is no defined "best team" in any Pokemon team. What your idea of a best team, may be different than someone else's idea. Use the Pokemon you like, and train them to high levels. You can use any Pokemon you want, as long as you teach them the right moves, you can't lose.
In my opinion, there is not a "best team". Take your most powerful Pokemon of major types, and battle with those.
swampert or blaziken are the best type to beat gyms or Pokemon league
There is no absolute best team. If you have 6 Deoxyses on your team and the opponent has one Darkrai, your team will essentially be destroyed. It all depends on diversity and which types of Pokemon you prefer.