Deluxe Paint III is very important for me. The features really showed the power of the Amiga.
My first professional animation I created with Deluxe Paint III on my Amiga 2000. I used a Genlock A2301 to mix a professional production.
Information:
https://en.wikipedia.org/wiki/Deluxe_Paint
http://theamigamuseum.com/software/applications/deluxe-paint/
http://www.computinghistory.org.uk/det/7875/Deluxe-Paint-III/