Infinite Resources (Can be used even when you have 0 of the currency):
Gold - Basic Currency
Rubies - Red Premium Currency
Dice - Used in Kingdom Adventure
Pickaxe - Used in the Underworld
Destiny Stone - Used in Grand Archives
Seed of Life - Used in Grand Archives
Fairy Stone - Used to level up Fairies and Pets
Random Stone - Grants Potential to Fairies
Enhancement Stone - Used to level up Equipment
Mileage - Premium Currency for spending $
Attribute Points - Character Advancement
Costume Ticket - Used to buy and upgrade outfits
Research Points - Used in the Research Lab
Guild Points - Used in the Guild Store
Limited Resources (You need the specified amount to use them):
Market Coin - Used in the Corgi Market
Hatch Accelerators (Common, Uncommon, Rare) - Used to speed up Egg Hatching (pets)
Dungeon Keys - Used for Random Stone, Enhancement Stone, Fairy Stone, Key of Life
Summon Tickets - Weapon, Armor, Fairy
If we could get Market Coins and Hatch Accelerators added to the Infinite List, that would be amazing. Will continue to update this, as we unlock more content, for what is and is not infinite.