Minior (5e Creature)
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Tiny elemental, any alignment
Shields Down. When the minior gets below half its hit points, its outer shell is destroyed. Its attack bonus increases by +2 and its AC decreases as stated above.
Tackle. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d6 + 2) bludgeoning damage.
Explosion. When a creature takes the killing strike against the minior, the minior explodes, dealing 13 (2d12) piercing damage as rock shards fly everywhere.
Minior are created in the atmosphere, unlike regular meteorites. The minerals in the atmosphere undergo some kind of mutation that grows into first a core, then a shell over the core, keeping the core safe from most dangers. On really extreme occasions, however, a minior could be found without the shell on it wandering around.