Blossom of Vanishment

You throw a glowing bud towards another creature, making a ranged attack roll using either your spellcasting modifier or dexterity. On a hit, you gain the Invisible condition until the end of your next turn and you teleport behind the target, which takes 3d6 piercing damage. Moreover, the next time you hit the target with an attack roll, you deal an extra 2d6 damage of the attack type. 

Using a Higher-Level Spell Slot. The initial damage or the extra damage (at choice) increases by 1d6 for each spell slot level above 1.