This effect shows off Point Gravity, which is a module that is only compatible with GPU particles. The module allows you to specify a point in space toward which all of the particles in that emitter will be drawn. It takes the place of the Point Attractor, Line Attractor, and Particle Attractor modules, which are only compatible with CPU particles. The Point Gravity module simply requires that you set up a position, a radius, and a strength.
The effect includes 2 Emitters:
One GPU Sprite Emitter that creates most of the visible particles in the effect and has Point Gravity and Collision (Scene Depth).
A standard CPU Emitter that emits only a few particles, but also uses a Light module, allowing the particles to spawn dynamic lights that illuminate the scene.
For more information on attraction modules, Attractor modules documentation.