DrawFighters (EP)

The easiest way to win 10 fights in a row is to finish off your first battle, then go to the gym and upgrade your characters with the character gems their earned to make them stronger. After you do that, just keep selecting training to go against the opponents you just faced to have an easier battle. Keep doing training battles while upgrading your character each time you level up until you have won 10 fights in a row and the trophy pops.