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Original Description:
 
When wandering in the underground caves of ponyvill, Maud came across a lost puppy. The puppy was chewing on rocks, it seemed to be hungry. Maud took the puppy home having a soft side for it since it seemed to be attracted to rocks. Trixie thought it was cute and it got along well with their son Moonstone. One day Rarity came to visit Maud and saw the puppy, now named obsidian. Rarity told her that that wasnt a normal do but a Diammond dog. Maud didnt care, she’d grown attached to him just like she did with her son. Moonstone and Obsidian became really close friends/brothers.