Everblobbing Gobhopper

You conjure a bouncing blob of gum in an unoccupied space on the ground within range, which fully fills a 5-foot cube. If a creature touches the blob or the blob enters a creature's space for the first time in a turn, the creature must succeed on a Dexterity saving throw or become stuck to the blob and become restrained. A blob can only restrain as many creatures as there is space around it (eight medium creatures for a 5-foot cube, twelve medium creatures for a 10-foot cube, and so on). As a bonus action on each of your turns, you can command the blob to bounce to a space on the ground within 15 feet, dragging any creatures restrained by the blob along with it. A creature restrained by the blob can use an action on each of its turns to make a DC 12 Strength (Athletics) check, freeing itself on a success.

At Higher Levels. When you cast this spell using a spell slot of 3rd-, 4th-, or 5th-level, the size of the blob is increased to occupy a 10-foot cube. When you cast this spell using a spell slot of 6th-, 7th-, or 8th-level, the size of the blob is increased to occupy a 15-foot cube. When you cast this spell using a 9th-level slot, the size of the blob is increased to occupy a 20-foot cube.