Armor Class 15
Hit Points 82 (15d6 + 30)
Speed 40 ft., fly 10 ft.
Saving Throws —
Skills Perception +5, Stealth +8
Damage Immunities bludgeoning, poison, psychic
Condition Immunities charmed, exhaustion, frightened, paralyzed, petrified, poisoned, prone, unconscious
Senses darkvision 60 ft., passive Perception 15
Languages understands one language of its creator but can’t speak
Challenge 5 (1,800 XP)
Bludgeoning Bounce (Orb Form Only). Whenever the quicksilver siege orb is subjected to bludgeoning damage, it takes no damage and instead is pushed up to 15 feet away from the source of the bludgeoning damage. If the damage is from a critical hit, the orb is pushed up to 30 feet.
Construct Nature. The quicksilver siege orb doesn't require air, food, drink, or sleep.
Flyby. The quicksilver siege orb doesn't provoke opportunity attacks when it flies out of an enemy's reach.
Immutable Form. The quicksilver siege orb is immune to any spell or effect that would alter its form.
Observant (Orb Form Only). The quicksilver siege orb has advantage on Wisdom (Perception) and Wisdom (Insight) checks. In addition, if the orb observes a creature for at least 1 minute, it has advantage on the first three attack rolls it makes against the creature.
Slippery. The quicksilver siege orb has advantage on saving throws and ability checks made to escape a grapple.
Multiattack. The quicksilver siege orb makes three Disk Blade or Slam attacks.
Disk Blade (Disk Form Only). Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 12 (2d6 + 5) slashing damage.
Slam (Orb Form Only). Melee Weapon Attack: +8 to hit, reach 5 ft., one target. Hit: 10 (2d4 + 5) bludgeoning damage.
Slashing Run (Recharge 4-6, Disk Form Only). The quicksilver siege orb flies up to 20 feet in a straight line, then it flies up to 20 feet in a straight line in a different direction. During this move, it can move through the space of any Large or smaller creature. The first time it enters a creature's space during this move, that creature must make a DC 16 Dexterity saving throw, taking 35 (10d6) slashing damage on a failed save, or half as much damage on a successful one.