Alpha 20.6 was a stable release in the "Alpha 20" series, which introduced massive overhauls to world generation (Random Gen), high-definition character models, and over 100 new points of interest (POIs).
When encountering this specific filename on third-party sites: FiИ™ier: 7.Days.to.Die.Alpha.20.6.b9.zip ...
Files labeled in this manner on unofficial sites can occasionally contain malware or modified code. Always scan .zip files with updated antivirus software before extracting them. Alpha 20