How Diablo 4's World Tiers work and where to change them.
Diablo 4 World Tiers offer different levels of difficulty, with higher tiers rewarding you with more gold and increased item drop rates. In past Diablo games you could change the difficulty fairly easily, but in Diablo 4, there's a lot more to Diablo 4 Gold it.
Every Diablo 4 player will start with two World Tier options: World Tier 1 (Adventurer) and World Tier 2 (Veteran). The options for World Tier 3 (Nightmare) and World Tier 4 (Torment) aren't available until you've completed the campaign.
For your first playthrough of Diablo 4, I'd recommend bumping it up to World Tier 2. Compared to the lower World Tier, Veteran adds a satisfying amount of friction to your first 50 levels. Enemies will attack you a little more and boss attacks will threaten you enough that you can't stand in place the entire time. As long as you pay attention to Diablo 4 Gold for sale your skills and practice evading attacks, World Tier 2 won't be significantly harder than World Tier 1 and will be a lot more engaging, too.