In Pet Simulator 99, diamonds are a valuable currency that can be used to purchase a variety of items, including pets, eggs, and upgrades. There are many different ways to farm diamonds in the game, but some methods are more efficient than others.
One of the best ways to farm diamonds is to complete quests. Quests are short missions that can be completed by interacting with NPCs or completing certain tasks. Each quest rewards a certain number of diamonds, and some quests even reward rare items. Quests can be found in the quest menu, which can be accessed by clicking on the quest icon in the top-right corner of the screen.