That was season 4 wasn't it? I'm still only on season 3 with the zombie students and Martin in the Japanese version. But from what I read about 4 with Edo... It sounds depressing.
Season 4 is all about depressing to be honest, since the entire plot was Darkness trying to control the world by taking over people via depressing illusion within World of Darkness
Even more depressing than being stuck in a desert with only bread and "soup gelatin" to eat while they hide from zombies. It is good, but it went from happy-go-lucky "get your game on" to dark kind of fast. I like season two the best so far.