Orcs Must Die 3 is an action tower defense game developed by Robot Entertainment. In this game, you need to defend your tower using various items. These items provide a stats boost and defend your rift from the orcs. All the items have their own upgrade and unique upgrades.
To unlock these special upgrades you need to keep on playing the game and collect skulls. The more perfect run you do each round the more skulls you receive as a reward. After each round, you would be able to access your book from where you can unlock all the items. You need to spend skulls for both the item and the special upgrade.
Orcs Must Die 3 Special Upgrade
While checking out the book and all the items available in it, you might see an icon with a special upgrade written on top of it but with a cross marked on the icon. Unfortunately, if you see an item with this cross marked on the special upgrade that means the item doesn’t have any special upgrade.
In this game, most of the items don’t have any special upgrades except the trinkets. Trinkets are the special items that use mana to cast a spell, give any special stats to the character, or to the rift. There is a total of 7 trinkets available in this game and their special upgrades are:
Healing Trinket – Increase the max health of the character
Empty Rift – The first enemy that goes into the rift is worth zero points.
Freedom Trinket – COOP player gets speed boost when breaking from stun.
Jar Of Ghost – Increase passive fear duration.
Ring Of Storms – Increase active storm duration.
Trap Reset Trinket – Reduce the cooldown of the trinket after use.
Mana Rage Trinket – The first spell after use costs zero mana.