Eevee (5e Creature)
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Small elemental, any alignment
Multienergy. As a bonus action, the eevee can grant itself resistance to one of the following damage types: acid, cold, fire, lightning, necrotic, psychic, or radiant. When it uses this feature, it loses any damage resistance it has been granted from this feature.
Adaptability. Once per turn, when eevee deals damage to a creature and has resistance or immunity to at least one damage type, it can choose to deal an additional 4 (1d8) damage of a type it is resistant or immune to.
Tackle. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage.
A confusing creature, the eevee is thought of an elemental without any elemental energy, however, it can transform into a number of creatures that represent many different energies. This potential is what makes it so powerful.