Dragon Cave is a game where you pick dragons from various caves and raise them to hatch. To hatch an egg, you just paste it onto any site, like a forum signature, and get people to click it! If they don't hatch within 5/7 days the egg will die.
You can pick various different eggs from different locations. Different eggs have different rarities. It's rarity system is similar to Chicken Smoothie's, except that rares are very difficult to obtain as opposed to CS. Once your dragon grows up, you can breed it!

These are my dragon eggs:

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