Once Eisen had a rather good, logical guess for what he was supposed to look for within these ditches, one after another, he squatted down in front of them and brought a bit of order into the ditches. With his Draconic Demon King form, he frightened the monsters within the ditches enough to have them be silent for a while, before he was able to talk to each of them individually.
This took Eisen quite a while, but at the very least it was better than nothing. Soon, however, the old man managed to stumble upon the first of the bunch that counted an 'Odd one out'. It was a monster that instead of promising Eisen random things, was actually asking him what he wanted to achieve. And after Eisen told him something random that maybe wasn't too far off from the truth, this monster made a proper suggestion for how it would be able to help.