Minecraft slime

Transparent. Even when the cube is in plain sight, it takes a successful DC 15 Wisdom (Perception) check to spot a cube that has neither moved nor attacked. A creature that tries to enter the cube's space while unaware of the cube is surprised by the cube.

Minecraft Physics. any creature touching the cube is dealt 1d4 acid damage.

Gelatinous regeneration. when the cube is taken out it splits into two smaller cubes, this process continues until a cube is shorter than 2 feet tall, once it is under 2 feet this ability is no longer in effect and the cube is destroyed.

hop. Melee Weapon Attack: +4 to hit, reach 5 ft., one creature. Hit: 10 (3d6) acid damage.

undeniable cuteness. if the cube is less than 2 feet tall it may use undeniable cuteness as a bonus action, every creature within a 5 foot radius is charmed unless it succeeds on a dc 15 wisdom saving throw, charmed creatures may retry the throw on their next turn, after three turns the effect disappears.