Heroes, upgrading and skills

The basics
When you open up your hero tab, you will see a list of 5 different items. Each with its specific purpose. This is where the upgrading happens. There are two ways to upgrade your heroes.
 * 1) Hero specific. You buy the upgrades with gold and these upgrades only last for the remainder of the current run.
 * 2) Random. By opening chests a random hero will be selected and a maximum of 6 items will be distributed at random as well. The big difference is, these upgrades last forever and will not disappear as soon as you loop.

Hero specific upgrades
This really doesn't require much explaining. You buy an upgrade and you gain a level for that item. At certain points you'll notice that an upgrade is much higher than expected. This is a key-point level and the next upgrade will add a significant boost.

Random upgrades
These do require more explaining. These upgrades last, however, these are not a 1:1 addition.

Permanent upgrades.
Unlike the hero specific upgrades, you will not keep gaining an item level for each item received.

Permanent upgrades happen in stages. There are different stages for the items as well. The higher your item level becomes, the more items you will need from the chests to gain a level. See the chart below for the numbers. If you look at the image on the right, you will notice the green numbers. These are the permanent upgrade numbers.

The sword is the dmg item. Meaning item 1. It requires 3 items to gain a level. You can check this both by looking at the chart above or by looking at the "Next permanent level up: 1/3" line. Should i want to level it up, i just need to buy 1 upgrade. However, seeing as i have 1/3 of the items required to gain another permanent level, i need 2 items from the chest for this item, in order to gain it.

Appearance
Next to the functional change of the items, there are also the tiny details in the game. Something which, in my opinion, should not be overlooked. With each change, the appearance of the item changes as well as the effect in the item-list. There is a different look for each of the 5 stages of the items. To show the difference, below a picture of both the ranger (left) and the huntress (right), as well as the different effects on the items (middle). These changes show in the item-list, the little photo of the hero in their home location, as well as on the battlefield.