Fiendish Creature (5e Template)
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Fiendish creatures dwell on the lower planes, the realms of evil, although they resemble beings found on the Material Plane. They are more fearsome in appearance than their earthly counterparts.
"Fiendish" is a template that can be applied to any corporeal aberration, beast, dragon, fey, giant, humanoid, monstrosity, ooze, or plant, hereafter referred to as the "base creature."
Type. If the base creature's type is aberration, dragon, ooze, or plant, the creature retains its type. Otherwise, the creature's type becomes fiend.
Damage Resistances. A fiendish creature is resistant to cold and fire damage, as well as to bludgeoning, piercing, and slashing damage from nonmagical attacks.
Damage Immunities. A fiendish creature is immune to poison damage.
Condition Immunities. A fiendish creature is immune to the poisoned condition.
Senses. The fiendish creature gains darkvision to a range of 60 feet. If the base creature has darkvision to a range greater than 60 feet, use the range for the base creature's darkvision instead.
Languages. If the base creature speaks at least one language, add Abyssal and/or Infernal to the list of languages known as appropriate to the fiendish creature's native plane.
Alignment. If the base creature has an alignment, its alignment becomes evil. (no change on the law/chaos axis)
Magic Resistance. The fiendish creature has advantage on saving throws against spells and other magical effects.
The fiendish creature's challenge rating requires recalculation if the base creature does not have both resistance to bludgeoning, piercing, and slashing damage from nonmagical attacks and the Magic Resistance trait.