Swarm of Manabane Scarabs

Limited Magic Immunity. The swarm of manabane scarabs can't be affected or detected by spells of 2nd level or lower unless it wishes to be. It has advantage on saving throws against all other spells and magical effects.

Sense Magic. The swarm of manabane scarabs senses magic within 120 feet of it at will. This trait otherwise works like the detect magic spell but isn't itself magical.

Swarm. The swarm can occupy another creature's space and vice versa, and the swarm can move through any opening large enough for a Tiny insect. The swarm can't regain hp or gain temporary hp.

Bites. Melee Weapon Attack: +5 to hit, reach 0 ft., one creature in the swarm's space. Hit: 28 (8d6) piercing damage, or 14 (4d6) piercing damage if the swarm has half of its hit points or fewer, and the swarm can attempt to end one random magical effect of 2nd level or lower on the target. This effect works like the dispel magic spell, except the swarm must always make an ability check. Its ability check for this is +5.

Drain Magic Item. The swarm drains the magic from one magic item in its space that isn't being worn or carried. A magic item with charges loses 1d4 charges, an item with limited uses per day loses one daily use, and a single-use item, such as a potion or spell scroll is destroyed. All other magic items have their effects suppressed for 1 minute. A drained item regains its magic after 1 hour.