I have an earth too ^^ i'm not sure if this will be any good advice, but i personally went for Vic, then scrolled her so she builds str ( i never have luck when it comes to builds ^^")

But there are other ones, depending on if you want to burst them or not, or how much you can get through to get them xD

In the end, there's Fred, Athena (not really worth it...?) :/, Eva (not the best attacker i guess... )and Roca (sorry if i missed any out) but not all of them work :/ I think it also depends on if ur earth is going into int or str :) hope this helped x_X