If you are looking for free particle effects in After Effects, consider using the built-in CC Particle Systems II or exploring legitimate free trials and alternative plugins.
For those who might not be ready to invest in the suite, there are free and open-source alternatives, though they might not offer the same level of functionality. Exploring these can be a good starting point for understanding what kind of effects and animations are possible. red giant trapcode suite 1604 with serial key cracked
