Fetus in a Jar, Greater (5e Equipment)
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Wondrous item, very rare (requires attunement by an evil-aligned creature)
This large glass vessel contains the stillborn fetus of a magically inclined race, typically a Tiefling. It has been enchanted and partially reanimated to be used as a magical weapon. This item holds 9 charges, regaining 1d6 after a short rest or 1d3+6 after a long rest. The fetus has 25 hit points, regaining 1d8 hit points after a long rest, and has an AC of 12.
As long as you are within 500 feet of this item, you may use a bonus action and expend 3 or more of its charges to cause the fetus to cast the spell Delayed Blast Fireball. This spell is cast at 7th level with a DC of 15, or at 1 level higher with a +1 to the DC for every additional charge used, up to 2.
The creation or possession of this item is prohibited, and generally seen as an abomination.