Anger is a great business, people will share it with you for free and if you're savvy enough, you can sell it back to them. The Rage Mages descended from Belligerus's early followers have found that modern world has just as much use for anger and magic as the ancient world.
at a place were magic gathers, for what ever reason, the trees of this place produce fruit that is filled with magic energies . these fruits when eaten cause different effects. much like the potion a wizard makes.