@Dave058182 Plants ARE indeed OP. But that doesn't mean you CANT beat them. I've reached Ultimate League 3 times in a row now, always with my Rustbolt control deck.
Let me tell you a little secret... This game is all about value. If you can outvalue your oponent, you'll win.
What do I mean by outvalue? Generally speaking it means: "Spending fewer resources in destroying a card than your opponent used to play it."
For example: If one of your zombies can trade 2 plants, you gain a small value. (2 cards to 1)
If you can kill a 3 cost card (Captain Cucumber) with a 1 cost card (Rolling Stone), you gain value.
If you kill a buffed plant (Lets say: Black Eyed-Pea + Fertilize (2 cards, 5 suns)) with just 1 card (Rocket Science or Alien Ooze, 1 card, 3 brains) you get DOUBLE value, both in cards and in resources.
That's how you win on this game.
If you look at my Rustbolt deck (link below) you'll see a clear pattern. I use the Black Holes and Landscapers (and sometimes even the Shrinking Ray superpower) to reduce the attack of all enemy plants, and then kill them with 1 Weed Spray.
However, you don't need to play a control deck in order to win.
Aggro decks also gain their own value.
Transforming 1 cost shrooms into 3 cost Pineclones is gaining value.
Killing a 3 cost plant (Sportacus, for example) with a 1 cost imp with deadly is gaining value.
Etc.
Long story short, identify why you are losing. Make a list if necessary.
And change your deck to try to counter what is killing you.
You don't need all the fancy legendaries, you just need to understand how the game works.
And don't let anyone tell you that you don't deserve Rank 50. You can do it, you just need more experience.
My deck: http://answers.ea.com/t5/General-Discussion/The-Ultimate-Control-Deck/m-p/6142302/highlight/true#M5707