Donating real-life money to Pokémon Crater - Battle Arena to help the site will grant you multiple benefits.
Credits[]
By donating you will receive credits, which you may use to either buy Elemental Maps, items, or (exclusive) Pokémon. Credits can also be obtained by logging in daily.
Upgraded yard[]
Donation will upgrade the maximum capacity of your Yard. Premium users will be able to release 1000 Pokémon into their Yards instead of 500 Pokémon. Super Premium users' limit will increase to 1500 Pokémon, thus increasing the chance of Pokémon encounters if they were to release that amount.
Donation Pokémon[]
With every donation you make, you will receive that day's Donation Pokémon. The Pokémon is usually a special Golden or Albino version. Donation Pokémon can't be released into one's Trainer's House, but they are available for trade.
Special encounters[]
After donating, you will either be put into the Premium or Super Premium group, depending on the amount of money you've donated to the site. Both will increase your Specials encounter rate. Check the Specials wiki for more information on odds.