Radan Sidhe (5e Creature)
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Tiny fey (sidhe), any non-lawful alignment
False Appearance. While the sidhe remains all on four, it is indistinguishable from an ordinary rat.
Little Bit Beastly. The sidhe is considered both a beast and a fey for any effect relating to its type.
Bite. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 3 (1d4 + 1) piercing damage.
Radan sidhes were not as lucky as their other beastly fey cousins. Humanoids often mistook them for common vermins, and drove them out of their civilization. Disdained by such hostile attitudes, radan sidhes found shelter in the sewers and attics, just like the vermins they hated so much.
Finding a radan sidhe in a city is not difficult; the difficulty comes from recognizing one. Radan sidhes know that their presence is not desirable for humanoids, so they prefer stealthy activities, taking only what they need when no one is looking. Maybe the rat you found in the drawer is one of the noble radan sidhe of your community block. Who knows?