After Gabriel Belmont destroyed the Forgotten One, he returned to the mortal realm and locked himself in this wing of the castle, where he lost his mind during the isolation. Eventually, he recovered, but he left the wing abandoned, forbidding his minions to travel there, leading to its current name.
Alucard is brought to this part of the castle by the Navigator in the Void Room, after placing the Void Sword for his father to find. This secret wing is mostly flooded by the castle blood, and cryptic messages are written in blood all over the walls and floors, presumably by Dracula during his madness.
Dracula's demented screams still echo through the halls, mostly unintelligible cries and the occasional bout of laughter, though he can be heard uttering "Marie..." every now and again along with some of his dialogue from Lords of Shadow.
Several messages can be seen written along the walls of the wing, spelled out in the blood that fills the halls and written in Latin:
- Ego vos omnes Interficiam (Lat: I will kill you all)
- Odium meum sempiternum erit (Lat: My hatred will last forever)
- Me vindicabo (Lat: I will have my revenge)
- Gabriel Belmont iam non est (Lat: Gabriel Belmont is now gone)
- Scio te adhuc (Lat: I know you still are)
- Vivere (Lat: Live (lit. to live)
- Scio te adhuc vivere (Lat: I know you still live)
- Te inveniam Zobek (Lat: I will find you, Zobek)
- Non refert ubi te celas (Lat: It does not matter where you hide)
- Fraternitas lucis semper damnetur (Lat: May the Brotherhood of Light be damned forever)
- According to the Navigator's fast travel map, the Forbidden Wing is located very close to Carmilla's Lair.
- In addition to the Latin messages, in one of the rooms, Marie's name is scrawled on the floor in blood as well.
- A statue of the Gorgon Sisters is found in the main chamber of the Forbidden Wing, holding the Chaos Claws. This shows a kind of reverse foreshadowing, hinting that the relic would eventually end up with Medusa in the City of the Damned. The blood that later floods the chamber is another foreshadowing to the ultimate fate of the Gorgon Sisters.