TwistedPretzel

What to upgrade next

1. 
   ZapLevel 12 → 13In 3 of your 10 best decks · 0.6 levels below those decks' average
2. 
   Electro WizardLevel 13 → 14In 4 of your 10 best decks
3. 
   Mega MinionLevel 12 → 13In 2 of your 10 best decks · 0.6 levels below those decks' average
4. 
   GraveyardLevel 12 → 13In 2 of your 10 best decks · 0.6 levels below those decks' average
5. 
   RageLevel 12 → 13In 2 of your 10 best decks · 0.6 levels below those decks' average

Based on the 10 best popular decks you can already play. The API doesn't include gold costs, so this ranks by how much an upgrade helps those decks, not by price.