Frostflame Reaver (5e Creature)
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Large elemental, neutral
Damage Resistances bludgeoning, piercing, and slashing from nonmagical attacks
Cold Absorption. Whenever the frostflame reaver is subjected to cold damage, it takes no damage and instead regains a number of hit points equal to the cold damage dealt.
Death Burst. When the frostflame reaver dies, it explodes in a blast of frigid wind and intense flame. Each creature within 10 feet of the frostflame reaver must make a DC 17 Dexterity saving throw, taking 36 (8d8) cold damage and 36 (8d8) fire damage on a failed save, or half as much damage on a successful one.
Multiattack. The frostflame reaver makes two attacks.
Slam. Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 15 (3d6 + 5) bludgeoning damage plus 7 (2d6) cold damage and 7 (2d6) fire damage.
A frostflame reaver is a dichotomous creature: a massive hulk of ice with a roaring inferno raging within, slowly melting its frozen shell, while tongues of fire dance out from cracks in the ice. The ice shell must be reinforced regularly by being subjected to intense cold. Without reinforcement, the ice shell usually lasts a few weeks before melting. When the shell breaks, the conflagration within the frostflame reaver is released, alongside a blast of intensely cold wind.
Elemental Nature. A frostflame reaver doesn't require air, food, drink, or sleep.