Lagging behind in levels, how do I catch up?

In my experience, it's fairly rare on "normal" difficulty to be too far behind the enemy level range to proceed. Here's what I normally do when playing through the game:

1. Explore each map fully. It's quite possible you missed some areas that have enemies or dungeons you didn't see.
2. Always complete the side quests in a given stage
3. Enter phase portal challenges when possible (go in prepared!)
4. If you stumble upon a dungeon that's too powerful for you at the moment, continue fully exploring the map. It's pretty easy to level up a few times on each map just by fully exploring it.
5. As a last resort, you can re-roll the world (as you did) and play through again.

The most fun way is to replay your favorite dungeons. Dungeons will re-spawn after 10 minutes if you enter another different dungeon. Most dungeon bosses will re-spawn with the dungeon.

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