Item description:

Gold - Metal God - Achieved 100% completion on the stats screen
Simply view the stats menu and the trophy will unlock.

Silver - I've never touched an axe before - Personally smoted 300 enemies - any mode
Kill any enemy with your axe for the trophy to unlock.

Silver - Favored - Acquired 3,000 fire tributes
Load the Tour of Destruction from chapter select & defend the bus in the short mission to get "Favored" trophy for acquiring 3000 Fire Tributes. (Credit PounDJo0DoGz0r)

Silver - Sellout - Spent 250,000 fans - any mode
Earn 1 more fan and the trophy should unlock.

Bronze - Some Demon Flesh on your Bumper - Slayed 150 enemies with Deuce - any mode
Just run over an enemy in the druid plower.