E1M6: Gateway Lab (Return to Hadron)

E1M6: Gateway Lab is the sixth map of Return to Hadron. It was designed by Matt Powell (cannonball) and uses the music track from Level 06 and Level 18 of TNT: Evilution.

Essentials
Blue key

At the start, you see a range of barrels that must be exploded to make you way. Do not explode them manually, using your inventory weapons, but instead approach them and you will discover two sergeants on both sides. Provoke them to shoot at you, so they will unintentionally hit the barrels that will kill both sergeants. If you fire any weapon on this level you will wake enemies which will later spawn in this area. Do not shoot unless you want a big combat. The blue key is already accessible in the north side of the map, so run forward to the north of the map. Do not also forget to collect items and weapons scattered throughout on the level. Once you will meet the blue keycard, placed on the blue cross-shaped floor, take it. Still, do not fire any weapon. Take the chaingun and backpack in the same room and turn right. Open the blue barrier (requires blue key) and press the switch behind. It will open numerous areas on the level, as well as will prepare hell spawn and sergeants to teleport in here once you use any weapon. In addition, a baron of Hell trap will open behind you, so do not get on his sight for now.

Yellow key

The key can be seen in the same room where the blue key was. However, barriers block your way. You need to press two switches that will lower these barriers:
 * 1) Head to the center of the map where BFG9000 can be seen trapped behind red key barriers. Turn right (west) and ascend the stairs. Then, turn left and ascend the other stairs. Head forward until you can see the first switch. Press it.
 * 2) Head to the center of the map again and this time head to the east. Ascend on the first staircase and on the second to the right. Ahead is the second switch. Press it.

After all two switches pressed return to the room where the blue key was. To the north is the raised platform with the key that can be lowered by pressing the button on it. However, if the baron of Hell did not see you once and walks somewhere around he can hinder you now. Press the switch and possess the key.

Exit

With the yellow key, go to the room that is located east from the blue key room (with cross-shape structure). There, turn left and ascend the stairs. Go to the exit door in front. There is the end of the level.

Secrets

 * 1) Go to the northern room with blue cross-shaped floor and blue keycard. Head to a room to the right, then to the right again. Go to the three barrels (if they are still here) and a human corpse. Turn right and you will notice a greenish brick. Lower it by pressing use. Beyond there is a switch. Press it and head back. The room which was observable through its window is now accessible. Go there and take equipment. (sector 290)
 * 2) Once you obtained the blue keycard and pressed the switch behind the blue key barrier head to the west and ascend the stairs until you can enter the western room. In that room you will see three square blocks one of which has a plasma gun and the others have tech columns upon. You need a block with a tech column which has another texture on one of its sides. Press use on this side to open a door leading to the secret room. (sector 109)
 * 3) Once you collected everything in secret#2 go out of the room and you will notice a dark switch on the wall. Shoot it and return back to the room. In the new opened room collect the red keycard, so you can access secret#4. (sector 105)
 * 4) Go to the center of the level where the red barriers are. Since you have got the red key in secret#3, open the barriers and collect BFG9000 and cells. This counts as a secret. (sector 12)

Things
This level contains the following numbers of things per skill level: