|The Ruins of Tribulation|
|Romaji||Shiren no Iseki|
|Previous Episode||The Seductive Witch|
|Next Episode||The Evolved Mage|
|Japanese||January 13, 2017|
|English||January 20, 2017|
The Ruins of Tribulation is the fourth episode of Koro-Sensei Quest!
The Class E and Korosensei are summoned by Gakuho Asano to a myterious dungeon, were they meat a Kunudon who makes Korosensei and Class E various obstacles and at the end the final obstacles which is to either sacrafice himself for teh students or press a button and save himself by being crushed, Korosensei pressed the botton and saved both himself and the students.