This level occupies the map slot MAP09. For other maps which occupy this slot, see Category:MAP09.
MAP09: Stronghold is the ninth map of TNT: Evilution. It was designed by Jimmy Sieben, with minor additions and touchups by Ty Halderman, and uses the music track "Sadistic". It is notable for having many enemies. This sheer number of monsters almost entirely consists of hitscan-employing troopers, sergeants and chaingunners, who will often take potshots at the player from balconies and through windows. Somewhat confined layout of the map also adds to its difficulty.
After getting the red key, you'll see a narrow hallway through a window to the right. Press the use key against the window to lower it, letting you access the hallway. There is a blur sphere at the opposite end.
In the same room as the first red switch (at the west end of the map) is a wall with flashing blue lights. Lower the wall with the lights like a lift to be taken up to a secret cache.
At the south end of the map is a long hallway with a series of silver doors you must open before getting a backpack on a pedestal at the end. When you pick up the backpack, several alcoves open in the hall behind you, releasing enemies. One of these alcoves has a triangle on its back wall; open it to access a secret area.
At one end of secret #3 is a second triangle on the wall; it acts as a lift up to a secret-in-a-secret, at the end of which you'll find a berserk pack.
At the north-northeast corner of the map is a room with a square sunken nukage pool. On the ledge in the southeast corner of the pool are two red lights visible in the walls. Open the wall between the lights to access a secret room
See secret #5 (the door and room sectors are both tagged as secret).
At the eastern end of the aforementioned nukage pool room is a silver alcove; step in to be taken down to a new area. In this green room, open the wall to the right (with yellow lights along the bottom) to activate another lift up to a secret area with two teleporters in it.
Inside secret #7 is a sunken brown floor alongside an "L"-shaped computer terminal. Stepping onto it registers a secret.
While still in secret #7, take the right-hand teleporter. It takes you to the raised area back in the green room.
Return to secret #7 once more, and take the left-hand teleporter. It takes you to a secret corridor all the way back near the level's start.
In the stairway leading up to the room containing the exit door, there is a wall with two blue triangles on it. Open it up to reach the last secret.
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Added by Fredrik
