I think a fun deck to play in the future would be the new Shedinja from Emerald break* and the Flashfire Floette with Flower Viel. For a single energy, as long as you have 40-50 damage and a few Floettes out, you can do 250 damage. The only problem is I don't know what card to play that could do damage to Sheninja, Maybe frozen city? I don't know how competitive this would be, but I think it would be fun. In expanded you could even run the Cast-off shell Ninjask to get Shedinjas out faster.
Shedinja - Grass - HP30
Stage 1 - Evolves from Nincada
[G] Curse Rain: Put 1 damage counter on each of your opponent’s Pokemon. Then, switch this Pokemon with 1 of your Benched Pokemon.
[C] Transient Cry: 50x damage. This attack does 50 damage times the number of damage counters on this Pokemon.
Weakness: none
Resistance: none
Retreat: 1
Shedinja - Grass - HP30
Stage 1 - Evolves from Nincada
[G] Curse Rain: Put 1 damage counter on each of your opponent’s Pokemon. Then, switch this Pokemon with 1 of your Benched Pokemon.
[C] Transient Cry: 50x damage. This attack does 50 damage times the number of damage counters on this Pokemon.
Weakness: none
Resistance: none
Retreat: 1