[REQUEST] Giving permissions when finishing objectives.

Heyya,
I've been working on a system for my server...
Player Titles, it works through the menu, where you have to buy titles or earn them throughout the server.
So.. I've run into a problem with the 'earn-able' titles, you can't make a menu option/command to give you the title. So i thought, what if you could get a the permission to use that command, from achieving that goal.
Is there any plugins, that could do give permissions once you've completed certain objectives like "Kill 100 Players, Play for 100 hours on the server, kill 100 mobs etc..)
Thanks, :')