Upgrade all of these items one after another for maximum benefit from your next run.
Want to increase your weapon-based score multiplier? Purchase new levels here to extend your multiplier.
The same effect as the Weapon Upgrade, but applied when you're smashing your way through obstacles and generally trashing the castle.
Investing into this category will make your Rampages last longer and have an enhanced multiplier effect.
Need more mana in your life? Throw some coins at this particular upgrade and they'll appear more often.
Spending money to make more money: ah, the joys of the upgrade store. Still, if you want to gather more coins from those precious treasure chests, upgrade their booty here.