Warlock's Tower (JP)

There are a total of 74 levels in the game that you'll need to complete for all achievements. As noted in the roadmap, the "?" levels in each area can be completely ignored, in terms of achievements. In the second section of each area, the stairs to leave typically become accessible without having to complete every numbered level. Make sure you complete every level before moving on though, so you don't have to backtrack later.

The video below, provided by user Baddriver, shows the level solution for all 74 levels in text format, making them extremely easy to follow. The NPCs are also included in their respective levels, assuring you'll get all achievements as you progress. The video description in YouTube contains timestamps for every level.