Another animation by the great Gabriel H Fermanelli done in After Effects and exported to svg.
It uses some AE expressions, sliders, time remapping and mainly solids and masks.
Note: Since this animation was not optimized for web animation, and uses hundreds of elements and hundreds of masks, it has some performance issues, but works fairly well on major browsers. Firefox seems to perform worse than the rest and IE has a couple more glitches than the rest. Haven't tried it in Edge.
Link to Gabriel's work: https://www.behance.net/gahfe