THE ESSENCE of Play2Earn is to make more than you spend, playing Splinterlands.

So, we want to MAXIMIZE our earnings- for each win.
While we MINIMIZE our spending, through rentals.
All, while ensuring we win enough games to get to Silver to start bringing in the serious DEC.

The best way to maximize your earnings, on each win, is to use Gold/Alpha/Promo cards. EACH card with one of these attributes, gives you a +10% bonus to your earnings.

That may not seem like much but imagine a scenario where you have a Gold Foil Summoner and 4 Gold Foil monsters- that's an extra 50% on your earnings for each win. For every 2 wins, you get paid for 3.

The best way to get cheap rentals on these cards, is through PeakMonsters (PeakMonsters.com).

They have a lot of very powerful tools to help you find, rent and extend your rentals.

So, go to Peak Monsters--> Rentals
On the right side of the screen- you'll see a bunch of filtering tools: Edition, General, Rarity, Splinter... You'll want a Summoner, first. So, select "Summoners" under General and since we're going to be building the pre-eminent Bronze/Silver deck- Select the Leaf icon under Element. This will limit the results to Earth Summoners and find you the cheapest one of each, currently available on the market.

Renting Your Summoner

Click the cart beside Mylor Crowling.
Click the cart in the header next to your name. (which should now have a little red circle on it "1")
Select a duration, click the blue or green button to pay with DEC or with Credits and BOOM! you now have a Mylor Crowling to use in your decks.

Getting the Rest of your Team

Now that we have a Summoner, time to get the rest of the team. De-select "Summoners" then select "Monsters" and "Gold" in General. Leave the Leaf selected under Elements but add Neutrals to the list. (crossed swords on the far right of the list)
Finally, click on Low Price (Level) at the top of the price column- his will sort your list of Earth and Neutral, Gold, Monsters by price/day- with the cheapest on top.
What you're looking for here are cheap, low mana cards you can use in your deck to boost both your winrate AND your earnings.
Two parameters For these cards:
Less than 10 DEC/day.
Less than 4 mana and useful.

Some Ideal Cards:

Goblin Dartling
Barking Spider
Highland Archer
Goblin Thief
Screeching Vulture
Goblin Sorcerer (available as Alpha- doubling your bonus!!)
Goblin Chef (PROMO!!!)
Etc.
IF there's a Unicorn Mustang, Sporcerer, or Furious Chicken available, cheaply enough, go ahead and pick those up as Gold too.

Two Core Cards to Get:

These are PRICEY, in Gold, so pick them up in Regular Foil. Just De-Select "Gold" under General on the right side of the list then look for Sporcerer and Furious Chicken. (as of this writing, they were 4 DEC/day) You may, also, want to rent a Wood Nymph.
Once you have those 2(3) cards- we're done with building the deck. It's time to PLAY!

Playing the Deck

Your standard line-up will be Unicorn Mustang, Chicken, Sporcerer, (Wood Nymph) then any of the Gold cards you have available, as mana allows.
Mylor Crowling, by himself, will allow you to destroy any melee you encounter.
The Sporcerer/Unicorn Mustang combo renders all Magic attacks harmless.
The Wood Nymph is there to Heal any damage your Unicorn Mustang does suffer while providing a bit of damage, herself.

Expected Results

Play about 60 games, winning around 90% of your games and you will be eligible to advance to Silver. (1,000 rating) Once there, you can either "Rent for Power" and Advance or stay in Bronze and continue to gain rating and DEC for Battles.

To me, the additional Chests from Daily Rewards and EOS are worth the cost of rentals to advance to Silver.

This deck, by itself, should be good enoug to propel you to Silver II or even Silver I (1,500-1,750 rating) just Battling on a daily basis. As your Rating increases, the Battle rewards increase- irrespective of your League but in Silver- the earnings/game pale in comparision to the gains through getting 2, 3, even 4 Chests from your Daily Quest Reward.

If you haven't already signed up for Splinterlands, or gotten your Spellbook, use this link:
https://splinterlands.com?ref=axrho
or just put my user name in the referral spot (axrho) and I can delegate a card for you to use for a season!