What would be the best team to get shadow mewtwo?

A few hours ago I got the tube pass but it was difficult and I wanted to know which would be the best?

If it is so difficult, what would be a good option for exchange.

or how can I train ev?

I have a brilliant strategy created by A_Wild_Derp_Noob_Appeared, perfected by Niyog, and broadcasted by Nir. See it here: https://cdn.discordapp.com/attachments/267186468944871424/701162405362925569/Battle_Frontier.png
It works best for the battle frontier (actually, I’m assembling the team right now, what a coincidence :D)

You can train EVs by going to the secret base and going to the ev trainer. If you don’t have a good secret base, come to mine- It has level trainer and ev trainer. Then, you can use Pokémon like Delta Gardevoir (Personally one of my favorite) to set up calm mind and sweep with thunderbolt and ice beam. If you don’t like that, then you could use dragon dance dragonite, the pidgey-endeavor-focus sash-quick attack “strategy”, if it even is that. Or you could use armored delta volcarona, azumarill for the tank, and some other good pokes. (I personally use primal Giratina, Azumarill, Mega Delta Gardevoir, Haxorus, Delta Charizard, Armored Flygon, and another Pokémon)

Dratini Playz that won’t work. The trainers at the Challenge Championship will outclass your strategies, even the sash-quick attack one. I’ve tried so many combinations and strategies, and so far, the only one that works is the one I linked. Also, Primal Giratina is banned in the Challenge Championship.