I loved the Phantasm movies back when I was a young punk. When Mind Flayers recently invaded my D&D campaign, I stole more than a few ideas.
Murder orbs are small constructs created by illithids and their alien science. These silvery metal orbs are made of a layered shell of mithril and adamantite around a core of humanoid brain matter and psionic circuitry. Murder Orbs typically patrol the shadowy corridors of illithid lairs or act as bodyguards for individual mind flayers. A high-status illithid is often accompanied by two or more Murder Orbs, which are easily hidden within the monster’s voluminous robes.
When a Murder Orb detects a target, it extends two extremely sharp, jagged spikes from its center and flies directly into its victim, impaling them and attaching to flesh and bone. Once secured, the Murder Orb extends a high-powered auger from between the spikes and drills into its victim’s flesh, causing further damage.
Tiny Construct, Lawful Evil
AC: 18 (natural armor + dexterity)
HP: 24 (8d4+8)
Speed: 60’ fly
STR: 4 (-3), DEX: 20 (+5), CON: 12 (+1), INT: 6 (-2), WIS: 16 (+3), CHA: 6 (-2)
Saves: Dexterity +7
Skills: Perception +5, Stealth +7
Damage Resistances: Bludgeoning, Slashing, Piercing from non-magical non-adamantine weapons
Damage Immunities: Cold, Lightning, Fire, Poison
Condition Immunities: Charm, Exhaustion, Frightened, Paralyzed, Petrified, Poisoned
Senses: Darkvision 120 ft., Passive Perception: 15
Languages: Understands Deep Speech, cannot speak
Challenge: 2 (450xp)
Spike. Melee weapon attack: +7 to hit, reach 5 feet, one target. Hit: 8 (1d6+5) piercing damage. On a successful hit, the Murder Orb attaches itself to its target. The Murder Orb’s movement drops to 0. The target or a nearby ally can use their action to try and remove the Murder Orb with a DC: 15 Strength check. The victim suffers 1d6 bludgeoning damage per removal attempt (successful or not). The Murder Orb can voluntarily detach from its victim as a Bonus Action (this causes no damage).
Drill. While attached to a target, the Murder Orb can use its action to drill into its victim’s flesh. This causes an automatic 2d6 piercing damage to the target.