While Particle Illusion 3.0.4 is a legacy version (originally by Wondertouch), current versions are developed by Boris FX. If you are using the classic version, "all extras" typically refers to the extensive and Pro Emitters collections. Quick Start Guide for Particle Illusion
ParticleIllusion 3.0.4 (pIllusion) represents a significant milestone in the history of 2D particle effects generation. Originally developed by wondertouch and later acquired by GenArts (and now Boris FX), version 3.0.4 served as the definitive standalone iteration for many visual effects artists. While modern post-production relies heavily on 3D-integrated particle systems, ParticleIllusion remains a vital tool for its speed, ease of use, and vast library of preset emitters. This paper provides an informative overview of the software’s architecture, specifically analyzing the mechanics of the 3.0.4 engine and categorizing the extensive "Extras" libraries that provided artists with thousands of ready-to-use effects.
The most important part of version 3.0.4 is the extensive collection of "extras"—thousands of presets released over years.