Smoke Construct (5e Creature)
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Medium elemental, unaligned
Damage Resistances lightning, thunder; bludgeoning, piercing, and slashing from nonmagical attacks
Air Form. The construct can enter a hostile creature's space and stop there. It can move through a space as narrow as 1 inch wide without squeezing.
Bound. The smoke construct is magically bound to a large bowl, which it was made in. As long as the construct and its bowl are on the same plane of existence, the bowl's owner can telepathically call the construct to travel to it, and the construct knows the distance and direction to the bowl. If the construct is within 60 feet of the bowl's owner, half of any damage the owner takes (rounded up) is transferred to the construct. The construct cannot move more than 300 feet away from the bowl.
Sneak Attack (1/Turn). The construct deals an extra 13 (4d6) damage when it hits a target with a slam attack and has advantage on the attack roll, or when the target is within 5 feet of an ally of the construct that isn't incapacitated and the construct doesn't have disadvantage on the attack roll.
Multiattack. The construct makes two slam attacks.
Slam. Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage.
Armor Removal (Recharge 4-6). The construct makes a melee attack action. Upon a hit, the target can make a DC 15 Dexterity saving throw, unless the target is prone, paralyzed, or otherwise unable. On a failure, the construct pushes a piece of armor off the target, causing it to fall straight to the ground.
Smoke Glide (Recharge 3-6). The construct collapses into the smoke carpet and is considered hidden. This action does not provoke attacks of opportunity. An attack made while gliding gains +3 to attack and damage rolls. The construct can remain hidden for 3 rounds. At the end of those rounds, the construct is forced into the open. This exit alone provokes an attack of opportunity with advantage. An early exit does not. A DC 25 Perception (Wisdom) check is required to see the gliding creature.
Smoke Constructs are the result of magical experimentation. Summoners began to notice that traces of air and fire elementals can be combined, though never naturally. The best method of construction was to simply combine the necessary ingredients in a large bowl. This bowl is then used as a phylactery. Should it be destroyed, the construct fades and dies immediately.
The smoke in the bowl flows out at the creator's command and lays on the ground, covering a 300 ft radius by default or whatever shape the creator declares upon arousing. The construct then emerges at a point of the creator's choosing, standing 6 feet tall, though still connected to the few inches of "carpet." All movement the construct makes must be within the range of smoke covering, whatever shape it may lay.
This creature cannot be summoned, but can be stored in any container that can hold 1 cubic foot of space or more. The creator must transfer the binding magics of the phylactery to the new container.