How many instruments do Du play?

Just one (at least for now just one). I play the Piano but I want to be able to play any other instrument and still be a pianist.

Right now just Cello, but I want to learn Piano too.

I play 3 instruments.
My primary instrument is the viola, but I also know how to play the Piano and the violin.
I also sing, but the voice usually isn't considered an instrument. If it was, Singen would be my primary instrument.