Custom Brushes and Tools Presets
https://gumroad.com/l/qAPcS
My custom brushes and tool presets I use every day for sketching and production. These brushes are the result of years of careful design oriented toward specific purposes.
The 30 minutes video introduce you to their organization and intended usage. It also covers the basics of the mixer brush and art history brush engines that I use quite a lot in my process.