The layer's sky was a shade of black that was reminiscent of venous blood.
The landscape was dotted with abandoned cities that served as shelters and hideouts for runaway petitioners, deserters, criminals, and lost creatures from other planes. Between cities, the layer was marked by surface mines, deforested areas, and clogged canals. Rivers were completely covered in sludge, and some areas contained sentient pieces of polluted matter that reached and grasped before dying from the toxic air. The few remaining forests were either in a state of rotting or spontaneously combusted. A black ichor exuded from all matter in the layer.
Maladomini was ruled by the fallen archon turned archdevil Baalzebul. In his obsessive quest for perfection, Baalzebul repeatedly ordered the construction of cities of increasing beauty and magnificence to serve as his seat of power. Invariably, he then grew unsatisfied with it and ordered that the latest city be abandoned and for a new one to be built. As of the late 14th century DR, the latest city under construction was Malagard.
Maladomini was once a beautiful and fully urbanized realm. However, Baalzebul, who at the time controlled both Maladomini and Malbolge, attempted to overthrow Asmodeus by forging and altering records in an attempt to frame Asmodeus as an incompetent leader. He then organized an attack on Nessus to replace Asmodeus before he could respond.
However, a massive offensive by demons from the Blood War upon Avernus occurred as Baalzebul was about to enact his plan. He instructed his legions to stay out of the fight, which caused the invading army to almost reach Dis. Baalzebul, finally, decided to order his legions to join the fight, but his delay caused suspicion from the other archdevils. When his treachery was revealed, Maladomini was ravaged by attacks from the other Lords of the Nine, which ultimately defeated Baalzebul and turned the layer into a devastated wasteland.
Asmodeus, knowing that Baalzebul's intellect would be useful to him, did not demote him, but enacted a punishment that included transforming the archdevil into a slug-like monster for one year for each lie he told to a devil, applied retroactively. This caused Baalzebul to remain in slug form for millennia, finally reverting back to his original form in the late 15th century DR.
- The Carnival Eternal, a grotesque amusement park created to reward devils for the souls they gathered.
- Grenpoli, the City of Diplomacy. A domed city where weapons and all types of aggression were forbidden, it contained the Political School of the Nine Hells, which offered courses on deceit and treachery to enterprising devils.
- Malagard, home to Baalzebul and the greatest city in the layer. Baalzebul's seat was located in the Palace of Filth.
- Offalion, a training facility designed to instruct devils on matters of political manipulation and bargaining by creating detailed simulations of locations in the Prime Material plane.
The layer was inhabited by numerous intelligent devils, such as amnizus, paeliryons, harvester devils, and erinyes, as well as ayperobos, barbazus, cornugons, lemures, and spinagons. The constant production of ichor also promoted the spontaneous generation of oozes, such as black puddings, gelatinous cubes, and ochre jellies.
- ↑ 1.0 1.1 1.2 1.3 1.4 Chris Pramas (1999). Guide to Hell. (TSR, Inc.), pp. 34–35. ISBN 978-0786914319.
- ↑ 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Robin D. Laws, Robert J. Schwalb (December 2006). Fiendish Codex II: Tyrants of the Nine Hells. (Wizards of the Coast), pp. 65–68. ISBN 0-7869-3940-0.
- ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Jeff Grubb, Bruce R. Cordell, David Noonan (September 2001). Manual of the Planes 3rd edition. (Wizards of the Coast), pp. 115, 121–122. ISBN 0-7869-1850-8.
- ↑ Richard Baker, John Rogers, Robert J. Schwalb, James Wyatt (December 2008). Manual of the Planes 4th edition. (Wizards of the Coast), pp. 97, 103–104. ISBN 978-0-7869-5002-7.
- ↑ Richard Baker, James Wyatt (March 2004). Player's Guide to Faerûn. (Wizards of the Coast), p. 161. ISBN 0-7869-3134-5.
- ↑ 6.0 6.1 6.2 6.3 6.4 Mike Mearls, Jeremy Crawford (May 29, 2018). Mordenkainen's Tome of Foes. Edited by Kim Mohan, Michele Carter. (Wizards of the Coast), pp. 15–16. ISBN 978-0786966240.