Inferno

Inferno is the third episode in Doom and Ultimate Doom. All of the levels in this episode are credited to Sandy Petersen, though Tom Hall originally began two of them. This episode is set in Hell, possibly the inner region of Hell. The episode is apparently named after Inferno, part of Dante Alighieri's Divine Comedy. "Inferno" also means "hell" in several languages. Most of these levels have a main, center room that can be easily identified, usually circular or square in shape.

Story
Having defeated the cyberdemon lord who ruled over the lost Deimos moon base, the Doom marine learns that the facility has somehow been teleported to Hell itself and used as the gateway enabling the demons' invasion of the Martian facilities. Determined to press on and learn the true source of the invasion, the marine must fight through the twisted reality of perdition itself. As on Deimos, the environment itself is deadly - volcanic plains, jagged rock, and barren scorching wastelands sprawl before him, punctuated only by looming, decrepit labyrinths dedicated to the worship of evil and the torment of the damned.

Eventually reaching the heart of Hell itself, its capital city of Dis, the marine confronts the mechanized abomination which masterminded the invasion plot, the spiderdemon. Using his newly discovered BFG9000, he leaves the creature nothing more than a charred wreck of tangled metal and splattered brain matter. A portal opens, revealing the green fields of Earth. Overjoyed, the marine steps through to return home, only to find that everything is not as it should be...

Levels

 * E3M1: Hell Keep
 * E3M2: Slough of Despair
 * E3M3: Pandemonium
 * E3M4: House of Pain
 * E3M5: Unholy Cathedral
 * E3M6: Mt. Erebus (Exit to secret level)
 * E3M7: Limbo
 * E3M8: Dis (Spiderdemon is boss)
 * E3M9: Warrens (Secret level)

Current records
The Compet-N records for the episode are:

The data was last verified in its entirety on February 23, 2013.