It's "César-Auguste-Jean-Guillaume-Hubert Franck - Sonata for Cello and Piano - IV. Allegretto poco mosso" performed by Paul Pitman, in the public domain ^^ As Paul Pitman is a piano player, I suppose he played the piano. He is listed as performer on musopen, they don't say who played the cello.
Yeah I was planning to add something like that. Any ideas? Like a magical, elven thing you need to be able to collect magma..?