Starting as a new recruit, you need to work your way up the ranks of the family to ultimately become the Godfather. There are others that stand in your way though, and these must be ruthlessly executed, for they will stop at nothing to remove you fro
You join each map as a new recruit, and get promoted by gaining kills. Promotion has its benefits (extra health, better starting weapons, ) & also its drawbacks (lower level kills give you less experience points).
Check the readme in the zipfile for comprehensive mod information, and install instructions.