The runaround begins from the second-floor balcony of Lobby 7, where it meets the Infinite Corridor. Walk down the Infinite to the Building 3 stairs, and ascend to the third floor. The gray sign is at the top of the stairs, behind a liquid nitrogen tank, and has "B" as its ninth character. Walk back towards Lobby 7, and take the elevator to the basement (using the "B" from the sign). Leaving the elevator, there is only one possible direction; this corridor intersects others at the Facilities Department's Customer Service Center, whose windows are printed with the names and numbers of all of MIT's buildings. Building 17 is the "Wright Brothers Wind Tunnel," so turn right. Almost immediately, an exit sign points left, down the basement level of the Infinite Corridor. Pass through the doors and across the road underpass to the courtyard parking lot, then back inside. When you reach the bottom of the Building 3 staircase, there is a large red-and-black fire panel, on which you can see that the "Heat Detector V/M #010" is in Zone 56. About 50 feet down the Infinite from here, a large black-and-red sprinkler pipe becomes visible overhead, leading left towards Building 13. When it is painted white, you're at the junction between Buildings 10 and 13; high along one wall is a pipe marked "RECLAIMED WATER FROM BUILDING 56," with an arrow pointing towards Building 13. This pipe enters a maze of other pipes, but can be traced to a tee just in front of a large, square, white tank. One branch of the tee leads into another tee with a large pipe, going into this tank, while the other heads down the hall towards Building 9. Following the shortest branch takes us into the tank, which is tagged with equipment number 734252.
The second image shows Buildings 31 and 39, as seen from the front of Building 13; this point is accessible just up the stairs to the west of the previous endpoint. Walk to the traffic gates, and then turn right into Building 24 (2×13−2). Along this hallway, there are illuminated signs near the ceiling, one of which reads "MAGNET IN USE." In the alcove below this sign is a conference poster, describing a superconductor with a chemical formula including O(6+δ). Further down the hall is a cabinet with orange labels, which inlude the word "MYLAR". Thus, turn left at the end of the hall, exit the building into the alley separating it from Building 34, and walk left towards the cryogen tanks. The oxygen tank has the descriptor "UN 1073" on it.
The third image shows the antique generator in the lobby of Building 36, also identifiable as the headquarters of the Research Laboratory for ELectronics. Go down the stairs from this lobby, and exit into the basement, then follow the corridor to the left until you reach a staircase up at the junction with Building 26. Continue into the Building 26 basement corridor, until reaching a spherical mirror at the junction with Building 32. Go left, and turn again at the next such mirror, now going northwards. Go up the next staircase, just past the second floor. A set of stainless steel doors between the second and third floors leads outside; take them, then immediately re-enter the building and ascend the stairs to the fourth-floor common. At the top, go back outside, then follow the exit sign into the covered stairway. At the bottom of these stairs, the number "666" is written on a column.
On reaching this point, solvers can proceed to the Mega Man round.
