DescentBB

This is my list of the very worst areas in the entirety of Descent 1. Keep in mind that it might not correspond to your own picks, but chances are they'll be similar anyway.

7th Place: Level 6's death trap area. Purposely designed to be aggravating, surprising and unforgivable, a blind player is practically guaranteed to die in this section at least once. On their 2nd try, they'll likely notice the invulnerability, but it'll probably take them many more tries to figure out there's a secret room with a cloak to be taken advantage of as well, so they can leave the invulnerability for the reactor room. It's at the bottom on the list as it can be handled with relatively little trouble with foreknowledge

6th Place: Level 19's yellow area - it's a horrible place, but the low number of robots you have to worry about makes it tolerable, and with enough patience, even easy. But it's way too terrifying to try and do any other way than by luring.

5th Place: Level 20's blue area - four lurking missile platformers ready to jump you and a very far dash towards the only available energy center in the level. Yeah, not much fun at all.

4th Place: Level 16's reactor area - with many roaming Super Hulks, very inconveniently placed matcens and a tempting to use invulnerability that can be squandered on the wrong robots, this area is quite tricky to get by, especially if you're doing a 100% run.

3rd Place: Level 11's reactor pit - Roaming hulks, a matcen to cut off your escape, melee robots to keep you in place. 'nuff said.

2nd Place: Level 17's blue area - A veritable death trap, all of it. The first section contains matcen traps that spawn either when you get back from the second part, or leave the area to go to the nearby energy center (which you'll inevitably need), so draining out the matcens is practically a must before you go further. But the second area is even worse - four chambers full of some the deadliest mechs in the game, who roam and try to catch you to boot. Fortunately the developers added a hack to the area, as there is an invulnerability behind a double secret door in the plasma driller chamber. Still your only chance is to open the doors with your nose while cloaked, otherwise you'll be long dead before you get the invulnerability. Without it, this is frankly possibly the hardest single area to clear out in the entire game, but just like with Level 6's death trap, some prior knowledge can make a lot of difference.

1st Place: Level 14's yellow area - with more Super Hulks than you can count, a sprawling network of tunnels also riddled with medium hulks, and a super hulk trap once you try to leave, this area is simply nuts. Requires thorough memorization and knowledge about the positions of the super hulks in the upper sprawling area to get both of them before they jump you from behind. There is a cloak and an invulnerability, but if you're approaching from the wrong corridor, you'll never even make it to the latter. The bottom pit isn't much better, but fortunately the super hulks from there have a tendency to come up and expose themselves. Not so with the medium hulks, who you can forget way too easily about.

There, this is my list of most hated areas in Descent. I'll be sure to make a list like this once I'm done with D2 and Vertigo too. In the meantime, let me know what your own most dreaded parts of the game are.

I don't remember 11's reactor having a matcen anywhere near.

Or hulks, for that matter.

I kinda meant the shaft that leads to the reactor room, that was not very precise wording

I have to check the editor now because the only matcen I remember in that part of the level does not stand between you and the exit...
EDIT: Checked, not only is there no matcen anywhere between reactor and exit on 11 the only robots guarding the reactor are bomb-laying drones. Are you *sure* 11 was the right level?

Alter-Fox, I think he is talking of the lava pit leading to the red door. The pit is close to the energy center.
Well I don't agree with some of the items (including 1-2) on the list, with some practice both areas can be done without problems. My list of traps and areas that contribute to most fails are (of course I am talking about 100% Insane no-save no death). Although I did not cold-started all the levels. Did 9,11, 19, 23, 24 cold start as far as I can remember.
1) Red area in L19 (cramped tunnels, red super hulk and a grey hulk, 2 small hulks and two plasma drillers). Still don't know how to not die there 4 of 5 times. Even with patient luring.
2) L23 - red area (with 3 super hulks and 5 drillers + some drones in the pit; and 2 matcens spawning melee robots). Those driller are nuts, even with fusion cannon and cloaking device against them.
3) L11 - Yellow key room (2 red hulks and 2 grey hulks in small room!). Disposing of 2 red hulks through the grate can be painful. Entering the room is just a Russian roulette, even with practice you can die instantly.
4) L19 - reactor room. Sure death without a cloak. 4 red hulks, 5 (or 6)? plasma drillers.
5) Maybe your item 5, L20 room with 4 platformers.
6) That lava tunnel area in L11 (need to be absolutely precise how to handle it, to avoid ambush by roaming robots. Personally, I start from getting the blue key, then blast red hulk with lava, shoot a mega into the lava pit (kill second red hulk), and clear the energy center (smart missile to kill 2 grey hulks). From there you can be relatively safe). The pit is relatively harmless, only problem you should lure most robots out, and then clear matcens first time from awkward position from above (to prevent red hulk attacking you), then I kill the red hulk in the bottom with lava or just corner snipe it, and clean the matcens 2 more times from more comfortable location near the bottom of the pit.
7) Initial interconnected area in L9. Took long time before I found relatively safe way to avoid being sandwiched by roaming robots there.
8 ) L24 - innermost ring. Roaming vulcan drillers, plasma drillers, Fusion hulks... But it is relatively easy if you use invuln from the beginning + cloaking device later; just need to handle vulcan guys and roaming plasma drillers as fast as you can.

1) Reactor room in level 1 D1 ( trainee )

Just bull★■◆●

You may want to play a different game.
@alex there's still no matcen in that area.

There totally is, it's in the uppermost part and it spawns class 1 dromes and red spiders. You get homing missiles in the alcove behind it.

I thought you said it was between the reactor and the exit?

No, I just said the matcen would cut off your escape, should you want to go back up. Which is true btw, it does activate from below too :<

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