Astrum Aureus

Astral Infection. A creature who hits Astrum Aureus with a melee attack must succeed on a DC 16 CON save or become temporarily infected with an astral disease. The creature has disadvantage on attack rolls and takes 10(4d4) necrotic damage on its next turn.

Standing Leap. Astrum Aureus can jump up to 20 ft high and 20 ft across without using any movement.

Jumping Smash. If Astrum Aureus jumps up to 15 ft into the air and lands in a creature's space, It can use Slam on all creatures it landed on and be pushed aside to the nearest unoccupied space.

Magic Resistance. Astrum Aureus has advantage on all saving throws against magical effects and spells.

Magic Weapons. Astrum Aureus's weapon attacks are magical.

Multiattack. Astrum Aureus makes two Astral Barrage attacks.

Charge. Astrum Aureus charges energy. While it is charging, its speed drops to 0 and its AC becomes 13 until the end of the round. It refreshes all its attacks when it is done charging, so it can use them again.

Slam. Melee Weapon Attack: +13 to hit, reach 10 ft., one target. Hit: 21(3d8 + 8) bludgeoning damage, and becomes temporarily infected with an astral disease. The creature has disadvantage on attack rolls and takes 10(4d4) necrotic damage on its next turn.

Astral Crystals(6/Charge). Astrum Aureus releases eight astral crystals from itself in all directions up to 15 ft. Each crystal then aims itself at the closest creature within 60 ft of it and attempts to slam into the creature. Each creature must succeed on a DC 16 DEX save or take 10(3d6) piercing damage. This damage is magical.

Astral Barrage(12/Charge). Astrum Aureus fires an astral barrage that pierces creatures. All creatures in a 90 ft line that is 5 ft wide must make a DC 14 DEX save or take 25(10d4) radiant damage on a failed save, or half as much damage on a successful one. 

Summon Aureus Spawns(2/Charge). Astrum Aureus summons two Aureus Spawns, which appears 10 ft from it in an unoccupied space. Each Aureus Spawn is a Small ooze, has 25 hit points, AC 19, has a flying speed of 50 ft, can hover, and takes 1 damage from any source of damage. Each turn, an Aureus Spawn must choose the closest creature to Astrum Aureus(not another Aureus Spawn) and must use all its movememt to get to that creature. If the Aureus Spawn gets within 5 ft of the creature, it explodes, and the creature must make a DC 18 DEX save or take 44(6d10) force damage on a failed save, or half as much damage on a successful one. If the Aureus Spawn cannot reach the targeted creature, such as when the creature has total cover or protected by a shield spell or similar effect, it explodes in its space, dealing no damage. If the Aureus spawn travels a total of 250 ft with its movement, it also explodes in its space, dealing no damage.