Board Thread:Series Discussion/@comment-918376-20160513012604

So we know that the Travelers didn't cause the Catastrophe (which they call the Eclipse). But they did purposely tangle themselves up in it because it was a "unique situation" that no other world had.

The Travelers want Empathiom. Empathiom comes from memories. Normally, people who die when they are killed, so they won't revive. This is true for us, for the Landers in Theldesia, and presumably whatever race created the Travelers (which is also apparently a race that cannot produce empathiom very quickly since they've run out of it).

However, after the Catastrophe, Adventurers have bodies that will always revive (barring certain circumstances), and they retain their memories, unlike monsters. That makes them an excellent source of empathiom, especially since they have memories of another world that they are forced to sacrifice in order to revive.

(Although Akatsuki stated that they willingly give them up in the final episode, it's suggested in volumes 6/7 that it's an involuntary process, and the Odyssey Knights in 8 wouldn't have to keep dying if they weren't forced to revive.)

In short, the Genius want to create a world of death so that they can keep killing Adventurers, forcing them to sacrifice their memories (give them Empathiom) in order to revive. And we don't know whether Adventurers are able to lose their memories of the Theldesian world because nobody has lost enough memories for that.

This isn't exactly any new information and most people have probably figured this out, but it didn't all click into my head until I was writing for my fan fic... 