Mana Wyrm (5e Creature)
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Tiny elemental, neutral
Bioluminescent. A mana wyrm is natural luminescent, and sheds dim light out to 5 feet. The more mana the mana wyrm has stored, the brighter it lights (up to 1 foot per mana point, minimum 5 feet as described above).
Magic Devourer. The mana wyrm can, when using its spell siphon ability, drain a spell slot from a target. It does not gain spell slots normally, and must feed on sources of spell slots.
Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 2 (1d4) piercing damage.
Mana Siphon. Melee Weapon Attack: +4 to hit, reach 5 ft., one target that has a spell slot. Hit: 2 (1d4) arcane damage, and the mana wyrm drains the magic essence from the target. Each successful siphon adds a 1st level spell slot.
Recovery. The mana wyrm can cast the mana rejuvenation spell.
Mana wyrms are simple, glowing critters that float around feeding off of stray pockets of arcane energy, clustering around places of power such as mana fountains. They can be familiars of spellcasters, but demand more upkeep magically-speaking (in terms of feeding them mana). Mana wyrms are usually translucently blue in color, but their color can change depending on the mana they drain.