Upgrade Attribute Bonus
Each upgrade level adds steps of +5% to the item's attributes: 1 step per level on Common and Uncommon items, 2 on Rare and higher.
How the steps are dealt
The steps are dealt in turn over the attributes in their tooltip order.
Example: a Legendary item with 5 attributes, from the first attribute to the fifth.
| Level | Attribute bonus |
|---|---|
| +1 | +5%, +5%, +0%, +0%, +0% |
| +2 | +5%, +5%, +5%, +5%, +0% |
| +3 | +10%, +5%, +5%, +5%, +5% |
| +4 | +10%, +10%, +10%, +5%, +5% |
| +5 | +10%, +10%, +10%, +10%, +10% |
| +6 | +15%, +15%, +10%, +10%, +10% |
| +7 | +15%, +15%, +15%, +15%, +10% |
| +8 | +20%, +15%, +15%, +15%, +15% |
| +9 | +20%, +20%, +20%, +15%, +15% |
| +10 | +20%, +20%, +20%, +20%, +20% |
Items that cannot be upgraded
Back items cannot be upgraded: "This item can't be upgraded."
Before a tradable item is upgraded, a prompt asks: "Upgrading makes this item untradable forever. Upgrade anyway?"