World of Warcraft item upgrade upgrades (relevant resource site)
item level upgrade upgrades are a way to boost the stats of an item. Based on the type of upgrade item you choose, it can boost the rarity of an item, or its Mark Level, and also boost other stats.
Upgrading equipment in The War Within requires a set number of Flightstones and Crests and each item upgrader mod comes with an upgrade track. Each upgrade increases the price of the next item by a specified amount.
Item Level
When an item is upgraded, its stats increase in value. This value is the sum of all of an item's leveled-up perks (attack magic attack and defense). The cost of upgrading items can be high, dependent on the upgrader and the kind of upgrade you decide to make. This is because of how many perks need to be replaced in order for the item to get upgraded.
It is also used to enforce gating requirements when waiting for dungeons, raids and scenarios.
Read more