The gates of Gehenna are guarded by two of the Seventy-Seven Devils: Astarte the Abyssal and Rostrum the Savage.
In Trails in the Sky the 3rd, Gehenna serves as one of the final dungeons that appears within Phantasma, making up the Seventh Plane. After confronting the Lord of Phantasma, who is revealed to be Rufina Argent, Kevin is cast down into its fiery depth with Reis, and forced to climb the long path facing down depictions of those he had slain in his duties. at the top, where the gates reside, Kevin Graham and Ries Argent confront Georg Weissman and the two gatekeepers. There is also another, deeper level of Gehenna known as the Abyss, later accessed for further training.
Another area associated with Gehenna is the shaft near the main entrance of the Sun Fort in Crossbell was considered the path toward Gehenna by the D∴G Cult, from which they could turn away from Aidios' influence to side with demons by performing "rituals".
While the version of Gehenna and the Seventy-Seven Devils encountered in The 3rd were later revealed to only be copies, there has been proof that Gehenna actually does exist. Examples of this are the real Seventy-Seven Devils manifesting in Erebonia and Crossbell after the Great Twilight begins and the Erebonian Curse allowing them to access Zemuria.
- The Territory of Gou of the Azure Tree is said to be another manifestation of Gehenna.
- In Judaism, Gehenna, also known as Gehinnom, is an afterlife of punishment and cleansing.
- The term "Gehenna" is the Jewish and Christian analogue of hell/the small valley in Jerusalem.
- In the Legend of Heroes series, there are some realms that are often the equivalent of the Underworld.
- Hades is an underworld dimension that lies "beneath" the world in The Legend of Heroes IV: A Tear of Vermillion. It is where Octum, the God of Darkness is imprisoned and is also the realm of the dead.
|Dominion||Ein Selnate (1st) - Thomas Lysander (2nd) - Kevin Graham (5th) - Barkhorn (formerly 8th) - Gaius Worzel (8th) - Wazy Hemisphere (9th)|
|Knight||Rufina Argent - Abbas|
|Squire||Cesar - Juno - Marcia - Ries Argent - Rosine - Scarlet - Ventus|
|Cathedrals||Grancel - Crossbell - Heimdallr - Bareahard - Roer - Haliask - Ardent - Saint-Arkh - Ordis|
|Chapels||Bose - Rolent - Ruan - Zeiss - Trista - Celdic - Legram - Leeves - Parm - Raquel|
|Concepts||Aidios - Artifact - Gehenna - Gralsritter - Merkabah - Sept-Terrion - Stigma|