Excalibur

Excalibur, more commonly known as the Sword In the Stone, is the sword that Wyatt recieves at the age of 1. At the time, his mother, Piper, is very distraught about him having the sword and says 'You aren't getting this until you're at least 18.' Piper originally thought she was the heir of Excalibur, but her real job was to pass it down to Wyatt. Piper showed signs of being taken over by the sword's power, making us assume Wyatt will as well.