The final instalment of The Original Astronist Lecture Series emerges as the Total Immersion into Astronism as based on the concept of immersion in Astronism. This presentation provides a comprehensive understanding of the Astronist belief system as it stands here at the end of the Founding era. At over 1,000 slides long categorised into 20 sections and hundreds of subsections, the content within this presentation is vast. From a full exposition on the Astrosoteriology and Astroeschatology to exploring the cosmology of Astronism to many other disciplines, this presentation embodies a suitable way of commemorating the end of the Founding era and commencing the beginning of the Establishment era.