Scion of Elemental Water (Charisma)

You’ve been exposed to the primordial magic of the Elemental Plane of Water, granting you the following benefits:

• Elemental Magic. You learn the thaumaturgy cantrip, using Intelligence, Wisdom, or Charisma as the spellcasting ability (choose when you select this feat).
• Wave Surge. You can use a bonus action to create a forceful surge of water directed at a creature within 15 feet of you that you can see. The target must make a Strength saving throw; the DC for this save is equal to 8 + your proficiency bonus + the spellcasting ability modifier chosen for this feat, and a creature can choose to fail this saving throw. On a failure, the target is pushed up to 10 feet away from you or pulled up to 10 feet toward you (your choice). The water vanishes immediately after the creature succeeds or fails. You can create this effect a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.