Weight Spike

You envelop your hand in a purple light and increase the pull of gravity on a creature you touch. Make a melee spell attack against the target. You have advantage on the attack roll if the target is wearing heavy armor or is Large or larger. On a hit, the target takes 2d4 bludgeoning damage, and its speed is reduced by 10 feet until the start of its next turn as its own weight pulls it down.

The spell's damage increases by 2d4 when you reach 5th level (4d4), 11th level (6d4), and 17th level (8d4).