Change the page's content: Charisma is the oni's natural Spellcasting ability (spell save DC 13). The oni has an intrinsic ability to perform the following spells, which need no material components: At any time: Darkness 1 each day: Charm Person Sleeping in a gaseous state: The weapon assaults of the oni are magical. If the oni has at least one health point, it regains 10 hit points at the start of its turn. The oni attacks with either its claws or its glaive: Melee Weapon Attack: +7 to hit, 5 ft. range, 1 target Slashing damage of 8 (1d8 + 4) on hit. Melee Weapon Attack: +7 to hit, 10 yd. range, one target. Hit: 15 (2d10 + 4) slashing damage in Small or Medium form, or 9 (1d10 + 4) slashing damage in Small or Medium form. The oni may magically transform into a Small or Medium Humanoid, a Large Giant, or its real form. Aside from size, its statistics are the same in each version. The sole piece of Equipment that gets altered is its Glaive, which shrinks to allow it to be used in Humanoid form. When an oni dies, it returns to its real form, and its Glaive shrinks to its usual size.
Armed only with their claws or a glaive. When feasible, the Oni will go forward in battle, isolating a single adversary. The first strike will come from invisibility, giving it the upper hand. When wielding the Glaive, it will be done so with both hands. Taking use of both the 10-foot reach and the significantly increased damage potential. When the adversaries are weak, these critters' claws are a lot more rewarding weapon. Remember that since the only can fly, they can travel about the battlefield easily and will often use their Glaive from above and beyond of reach of their adversaries. Because missile weapon wielders and spell-users make this technique substantially more difficult, they are prime targets for the Oni.
Choosing the monastic tradition that your DND monk follows will benefit you even in roleplaying.
For example, as I type this, I'm playing a monk character that follows the monastic tradition of the Way of the Drunken Master, and it's a lot of fun to make him tipsy just before combat so he can go and do strange things.
This monster may be a powerful and dynamic solo boss encounter for groups of levels 7 to 9, or it can be coupled with another villain or groups of villains in a single encounter for even higher level parties. As a solitary encounter, the oni nightblade may maneuver in and out of battle creatively, hiding when it needs to replenish and ambushing the PCs one by one as it glides through darkness, fading in and out of view. They may be utilized as the villains themselves or as the great bad's right hand. They also work well with strong villains like devils (who have Devil Sight and can see through onis darkness), chromatic dragons (whose blindsight cuts through magical darkness), drow, liches, and other evil beings. The most dangerous and powerful of these clients may employ a large number of nightblades at once, even hiring the whole Shadow Clan for short periods of time. While the cost in currency and magic is high, the advantages in information, espionage, and personal protection provided by so many nightblades are practically unsurpassed. D&D Beyond: Oni Nightblade PDF Link
