Arcane Bomb

You touch a creature, object, or surface, placing a mark of explosive arcane energy on them. If you are targeting a creature, you make a melee spell attack against that target. From your next turn onwards you may, as an action, activate this mark. The marked target and all creatures and objects within a 20-foot radius around the marked target take 6d6 force damage and are pushed 10 feet away from the point of origin and knocked prone. The marked target is pushed based on where the mark is placed, for instance if on the front, they are pushed backwards. Creatures may make a Strength saving throw for half damage and are not pushed back nor knocked prone. The spell ends when the mark is activated.

If an object or surface had mark placed on them for this spell, it takes double damage.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.