The Swamp of Sadness

The Lake of Sadness is episode 39 of Ultraman Gaia

Heroes
Ultraman Gaia

Monsters
Tsuchikera

Trivia

 * This was one of the sadder episodes because of the horrible thing that happened to the old man's friend during the war since he was used by force as a test subject and turned into a monster and that he could never see his family again
 * Also to note this was the first war plot in this series