I shall assume you meant to have an Earth mark there. So, what do you need help with? What's your goal with it? I can safely give you a couple general ideas, I guess. If you want to speed it up: 3-4 Minor Phoenixes, 4 Photons/Ball Lightnings (the latter are really cool for pulling off 3-turn wins, 1-2 Gavels, 2-3 Crimson Dragons (not Ruby, they're slower), 7 towers, no Pendulums and no shield.
If you want it more versatile, remove two dragons and two towers for 2 Rage Potions and 2 Deflagrations. It's not really needed for T50 though; not with that speed.