Aqueous Alloy

Amorphous. The alloy can move through a space as narrow as 1 inch wide without squeezing.

Spider Climb. The alloy can climb difficult surfaces, including upside down on ceilings, without needing to make an ability check.

Free Flowing. The alloy can freely move through another creature's space, and any space it occupies is considered difficult terrain.

Magic Sense. The alloy can sense creatures that have unused spell slots within 120 ft of it.

Absorb Magic. When the alloy takes acid, cold, fire, force, lightning, necrotic, poison, psychic, radiant, or thunder damage it will gain resistance to that damage type. If multiple types of damage occur at the same time, whichever did the most will be absorbed. The resistance remains until the alloy is dealt a different type of damage, gaining resistance to that instead.

Pseudopod. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) bludgeoning damage. If the alloy has resistance to a damage type from Absorb Magic, the attack also deals 3d6 damage of the absorbed type. Creatures that are large or smaller must succeed on a DC 14 Strength saving throw or become grappled and restrained. If the creature is occupying the same space as the alloy it has disadvantage on the saving throw.

Drain Magic. As a bonus action, the alloy attempts to expunge magic energy from a creature it has grappled. The creature must succeed on a DC 14 saving throw or lose one of its highest leveled spell slots. The saving throw type is whatever stat the creature uses for its spell casting. If a spell slot is absorbed, the alloy immediately heals 5 hit points per level of the spell slot.