Fire/Water Deck

I built this deck off the White Kyurem Deck. Here it is

Pokemon
Keldeo EX x1
Heatran EX x1
Keldeo x1
White Kyurem x1
Tepig x1
Pignite x1
Flareon x1
Eevee x1
Vanillite x1
Vanillish x1
Vanilluxe x1
Ducklett x1
Swanna x1
Tympole x2
Palpitoad x1
Kyurem x1
Charmander x2
Charmeleon x1

Fire Energy x10
Water Energy x10

Trainers

Pokeball x2
Switch x1
Team Plasma Ball x1
Pokemon Communication x3
Energy Retrieval x1
Superior Energy Retrieval x1
Potion x2
Energy Search x1
Super Rod x1
Hypnotoxic Laser x1
Colress x1
Cilan x1
Team Plasma Grunt x1
Shadow Triad x1
Professor Juniper x2

I don't have many cards and this is the best I can do right now with my cards. Any chance this could be good?

Sorry but most likely not. Having only one of each pokemon, would make your deck completely unreliable. Especially with so many lines of pokemon. If possible, make your deck have multiple of the same pokemon, so you have better chances of pulling the one you want, and better chance of it not being in your prize cards.

While i'm not the best at deck construction yet, as i have only just started playing again last month or so. I try to shoot for 2 or 3 lines of pokemon that evolve and a few good basic pokemon to fill it out. My decks usually end up having around 17 pokemon. Keep in mind that its not a professional tournament deck or anything. But it gets the job done.

Your success rate will be inconsistent in casual play and will be non-existent at most tournaments and leagues, unfortunately. This is due to a lack of focus on specific evolutionary lines like Profen above me has said. Pick a few Pokemon that look like they would combo well together or that you like and focus on building everything in your deck around them, and bulk up the evolutionary lines of those core Pokemon to at least 2 of each stage, preferably to 3 or 4 on the most vital Pokemon.

Also, add more Trainers, especially supporters like Professor Juniper and Skyla. These will help the consistency of your deck as well.