SilentDawn’s review published on Letterboxd:
Easily one of the weirdest shorts I've ever seen. I've been debating for the past few days on whether I even liked it or not, and although it is quite annoying in stretches, I found the film as a whole to be sweet and calming in the best way.
Several compositions in Lava are absolutely stunning, and with the combination of the miraculous animation, the finished product looks gorgeous. Although I don't want that song stuck in my head, I can't wait to watch this again just for some of the most haunting imagery in a Pixar short.
Also, the majority of my audience was crying by the end of this. Trust me, I swear Pixar just put this short in front of Inside Out as a way of preparing you for the emotional devastation of the main feature.