Yellow is Beaten! (finally) And this time, the team is Pokemon X!
Greninja
(http://orig00.deviantart.net/c749/f/2015/122/9/7/greninja_by_vale98pm-d6t9w75.png)
Surf
Waterfall
Dark Pulse
Ice Beam
Item: Amulet Coin
Ability: Torrent (won't do protean due to 3-minute soft resets in this game to receive starter)
Charizard
(http://pokecharms.com/data/attachment-files/2015/07/209048_Mega_Charizard_X.png)
Swords Dance
Flare Blitz
Dragon Claw
Fly
Item: Charizardite X
Ability: Blaze (Tough Claws when Mega)
Aegislash
(http://img.pokemondb.net/sprites/x-y/pixel/aegislash-shield.png)
Shadow Ball
Sacred Sword
Flash Cannon
King's Shield
Item: Spell Tag
Ability: Stance Change
Espeon
(http://pldh.net/media/pokemon/gen4/hgss/196.png)
Psychic
Morning Sun
Dazzling Gleam
Psyshock
Item:TwistedSpoon
Ability: Magic Bounce
Ampharos
(https://img.pokemondb.net/sprites/platinum/normal/ampharos.png)
Thunderbolt
Protect
Dragon Pulse
Power Gem
Item:Quick Claw
Ability:Static
Krookodile
(https://img.pokemondb.net/sprites/black-white/normal/krookodile.png)
Earthquake
Outrage
Crunch
Brick Break
Item:King's Rock
Ability: Moxie
Good team but I recommend adding Talonflame and a Speed Boost Blaziken with Power Up Punch. They will help you tear through the Gyms. Lucario and Mega Lucario with Power Up Punch will also work if you can't get Speed Boost Blaziken.
I do not have access to Speed Boost Blaziken, and why have a Talonflame when I'm picking Charizard as my second starter?
Talonflame has access to Steel Wing without using the TM and if you add Flame Charge, it can be a pretty effective sweeper. You can take out many Pokemon with a good Talonglame in just one or two turns. And like I said before, Lucario with Power Up Punch is also quite handy.
you're incredibly weak to ground after charizard mega evolves and loses its flying type, so you might want to consider charizard y. Since you're playing x youd have to get a mega stone from someone else, but somebody on the forums or in showdown's wifi room, etc or something could probably help you with that
If I knew how to breed and had the patience for it, i'd gladly provide the Yugioh 5D's chicken, but alas I don't. TBH i'd dump the charizard for talonflame to help with the ground weakness, and I didn't use the lucario for my playthrough but i've heard it's very helpful.
Actually, Charizardite Y is version exclusive. It's impossible to get the mega stone in this game, and at the moment I cannot trade with myself.