Mordekaiser Could Cure Depression

We know that everyone in Mitna Rachnun is bound to Mordekaiser's will, to the point where they won't even move without his order (at least sometimes). He has direct control over all of their souls, as evidenced by him turning a whole bunch of 'em into bricks.

So he could, in theory, use that power to tell them to stop being agonized over their existence. What are they going to do, disobey him? They'd have no choice but to feel whatever way he chooses to make them feel. He's not going to use his power for that, but he could.