A short, grey stone door blends into the wall at the end of an alley near the Lakeside end of Level 5. It bears no number, only an infinity symbol inscribed in the middle, at eye level for a dwarf. Nobody remembers seeing this door, as the infinity symbol acts as a permanent modify memory effect that edits the door out of the memory of anyone within 30 feet who sees the symbol or touches the door, then compels them to turn back to the main street and walk toward the Lift (needs 2 saves: Int DC 23 to negate each effect).
The door has no handle on the outside, only a keyhole covered by a tiny rotating stone panel. The small stone key etched with an infinity symbol exists on a large keyring marked "Lost Keys", hanging in a closet in one of the many warehouses somewhere on the College campus. The lock takes great effort to pick (DC 30, and the Symbol will force two saving throws every round), and the counterweighted door will take a full round to open once unlocked. The door will swing closed if not prevented. A conventional doorknob allows an easy exit to anyone trapped within.
The door opens, exposing a short hallway that leads into a small room with a hammock, a chair, a short table, and a small wardrobe along one wall. The other wall has a small kitchen area with a sink, small counter, wall cabinet (containing long-molded food, well organized), and a cubicle containing a toilet and shower that runs off the Sluiceway just underground. It looks as if the room hasn't been disturbed in years, except for some demonic-looking footprints leading from the back of the room to the exterior door.
A hidden door at the back of the room opens into a much larger room containing many shelves crammed with jars, boxes, bags, and various magical-seeming junk. Most of these items pertain to summoning or entrapping extraplanar creatures, though many cursed and harmful items lie on the shelves here as well. A broken clay jar scribed with runes lies shattered on the floor between rows of shelves, leaving a large gap on a middle shelf.
A round platinum medallion stamped with an infinity symbol within an eye hangs from a leather cord behind the storeroom door. If worn, it will negate the effects of the symbol on the door's exterior.
A small leather-bound journal hides behind a panel in a side of the wardrobe. It contains a long list of entries in a simple substitution cypher. Once translated they contain dates, locations, names (mostly demon names or monster names), and a letter plus two number code corresponding to the shelving unit, shelf height, and location on that shelf where whatever artifact from that encounter still exists. Doing some research will reveal the name Krannock Steelshanks, a missing Mountain Dwarf Abjurer who specializes in artifact recovery.