Dread Oni (5e Creature)
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Large giant, lawful evil
Saving Throws Dex +5, Con +8, Wis +6, Cha +7
Brute. A melee weapon deals one extra die of its damage when the oni hits with it (included in the attack).
Innate Spellcasting. The oni's innate spellcasting ability is Charisma (spell save DC 15). The oni can innately cast the following spells, requiring no material components:
Magic Weapons. The oni's weapon attacks are magical.
Multiattack. The oni makes three melee attacks, either with its claws or its glaive.
Claw (Oni Form Only). Melee Weapon Attack: +9 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) slashing damage.
Glaive. Melee Weapon Attack: +9 to hit, reach 10 ft., one target. Hit: 21 (3d10 + 5) slashing damage, or 16 (2d10 + 5) slashing damage in Small or Medium form.
Change Shape. The oni magically polymorphs into a Small or Medium humanoid, into a Large giant, or back into its true form. Other than its size, its statistics are the same in each form. The only equipment that is transformed is its glaive, which shrinks so that it can be wielded in humanoid form. If the oni dies, it reverts to its true form, and its glaive reverts to its normal size.
Leadership (Recharges after a Short or Long Rest). For 1 minute, the oni can utter a special command or warning whenever a nonhostile creature that it can see within 30 feet of it makes an attack roll or a saving throw. The creature can add a d4 to its roll provided it can hear and understand the oni. A creature can benefit from only one Leadership die at a time. This effect ends if the oni is incapacitated.
Parry. The oni adds 4 to its AC against one melee attack that would hit it. To do so, the oni must see the attacker and be wielding a melee weapon.
An oni with the Master template applied to it. Dread oni are fearsome creatures, even among the already terrifying oni. They lead other oni through force of will and intimidation on raids that can decimate entire countrysides, before vanishing almost as quickly as they appeared. They rarely enter combat themselves, preferring to gaze at the treasures they amass, but when they do, they can destroy opponents. They crave magic just as much as any oni, however, and so can easily be pressured into service themselves by hags and evil wizards.