I have recently started a new account to play with some new recruits to this game. Having only played with upgraded cards, it can be frustrating to start from scratch. I tried many different colors, but have finally settled on mono green. I have started 19-0 with no close matches and 3 elemental masteries. The most recent 15 matches are against Level 3, and the most recent 13 have the final deck configuration:
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4t3 5bs 5bs 5bs 5bs 5bs 5bs 5bs 5bs 5bs 5bs 5bs 5bt 5bt 5bt 5bu 5bu 5bu 5bu 5bu 5c0 5c0 5c0 5c0 5c0 5c2 5c2 5c2 5c2 5c3 5c4 5c6 5c6 5c6 5c7 5c7 5c7 8pn
Some tips:
Your hardest hitters are horned toads with adrenaline - this changes if the opponent puts out a shield.
Put out your weakest creatures first, even if you can afford the more expensive ones - this is to pull out your opponents anti creature cards.
Use adrenaline on your right most toad - the AI will stupidly target equal creatures from left to right and not factor adrenaline into the calulcations.
Adrenaline is ignored by the yellow bar when estimating your damage - take this into account when deciding when to play your heals in order to maximize your money gains and score.
Adrenaline is your friend against ice and your enemey against fire. Your creatures will unfreeze in one turn with adrenaline, but will get hit multiple times by a fire shield. Infections will only go off once.