Transistor from Bastion developer Supergiant Games.
Red, a young singer, has come into possession of the mysterious Transistor. The Transistor is a powerful talking sword. The Process wants both her and the Transistor and is relentlessly pursuing her.
[Edit: I made a stupid mistake and typed Braid, even though I knew better and was thinking Bastion. I’ve even been saying Bastion in conversation. It’s been corrected above and thank you to those who pointed it out.]