Netherworld Research is a passive activity where you send out units to explore other Netherworlds. Your units will automatically battle enemies and return with various rewards, including EXP, Mana, HL, and unique items. This is an excellent way to level up characters you're not actively using or to gather resources while you focus on other tasks. The success and rewards of research depend on the units you send, their levels, and the duration of the expedition. You can unlock more research slots and destinations by progressing through the story and passing bills in the Dark Assembly. Regularly check on your research teams and send them out on new expeditions to maximize your passive gains.
