Season 12 leveling in Diablo 4 is only painful if you play it like a slow, careful campaign run. After a few characters, you realise speed is the whole trick: keep moving, keep fighting, and don't babysit your inventory. If you're already thinking ahead to gearing and trading, it can help to know the best place to buy diablo 4 runes so you're not scrambling later, but right now your job is...