“+13 max resources” means your character’s maximum resource pool is increased by 13. In Diablo 4, that resource is the class meter you spend on skills, like Fury, Mana, Spirit, or Energy.

What it does

  • It lets you store more resource before hitting the cap.
  • That can help you cast more skills in a row, or keep certain builds working better when they need a larger resource pool.
  • It does not directly increase resource generation; it only raises the cap.

Simple example

If your max resource is 100 and an item gives +13 max resource, your cap becomes 113. That extra 13 can be enough to activate or sustain certain build effects that depend on having a higher resource total.

Where it comes from

Players report getting max resource from gear affixes, paragon nodes, skills, uniques, and masterworking on eligible items. A database entry also shows maximum resource affixes can roll in a range like +10 to +15 on some items.

TL;DR: it means your resource cap is 13 higher, which is usually useful for build requirements and smoother skill usage.