One of the most ignored systems is the barter vendor tied to Diablo 4 Gold mercenary progression.
As your mercenaries level up, this vendor unlocks high-value caches that can contain:
Boss summoning materials
Forgotten Souls
Veiled Crystals
Masterworking materials
Obols
Occasionally, even rare endgame keys drop from these caches.
Most players overlook this entirely-but it's one of the most consistent passive resource sources in the game.
Don't Skip Vendor Rotations Before You Start Playing
Temenos also hosts rotating vendors for weapons, armor, and jewelry.
What makes them important?