Now you have to nuke the Mastermind (not the Cyberdemon). I found stairs down at the bottom right of the Cyberdemon level.
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DoomRL (v.0.9.9.5) roguelike post-mortem character dump
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John Romero, level 10 Cacodemon 2nd Lieutenant Scout,
sacrificed himself to kill the Mastermind on level 8 of Hell.
He survived 15872 turns and scored 35815 points.
He played for 24 minutes and 8 seconds.
He didn't like it too rough.
He killed 32 out of 511 hellspawn. (6%)
My, was he a wimpy chump.
He was an Angel of Pacifism!
-- Special levels --------------------------------------------
Levels generated : 11
Levels visited : 6
Levels completed : 0
-- Awards ----------------------------------------------------
Minor Icarus Cross
Major Icarus Cross
Compet-n Silver Cross
Heroic Silver Badge
Pacifist Silver Badge
-- Graveyard -------------------------------------------------
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-- Statistics ------------------------------------------------
Health 0/70 Experience 1458/10
ToHit Ranged +0 ToHit Melee +0 ToDmg Ranged +0 ToDmg Melee +0
-- Traits ----------------------------------------------------
Class : Scout
Ironman (Level 2)
Hellrunner (Level 2)
Tough as nails (Level 2)
Dodgemaster (Level 1)
Intuition (Level 2)
Badass (Level 1)
HR->Int->HR->DM->Int->TaN->TaN->Bad->Iro->Iro->
-- Equipment -------------------------------------------------
[a] [ Armor ] green armor [1/1] (13%)
[b] [ Weapon ] nothing
[c] [ Boots ] protective boots [2/2] (100%) (A)
[d] [ Prepared ] nothing
-- Inventory -------------------------------------------------
[a] blue armor [2/2] (98%)
[b] red armor [1/4] (3%)
[c] small med-pack
[d] small med-pack
[e] small med-pack
[f] large med-pack
[g] phase device
[h] power mod pack
[i] power mod pack
[j] technical mod pack
[k] shockwave pack
[l] steel boots [1/1] (78%)
[m] protective boots [2/2] (70%)
-- Resistances -----------------------------------------------
Bullet - internal 0% torso 15% feet 0%
Shrapnel - internal 0% torso 15% feet 0%
Acid - internal 0% torso 0% feet 25%
-- Kills -----------------------------------------------------
4 former humans
4 former sergeants
2 former captains
5 imps
3 demons
13 lost souls
1 Spider Mastermind
-- History ---------------------------------------------------
On level 4 he stormed the Chained Court.
On level 8 he encountered the Phobos Anomaly.
He left level 13 as soon as possible.
On level 13 he found the City of Skulls.
He fled the City in terror!
He left level 14 as soon as possible.
On level 16 he found the Tower of Babel!
On level 17 he invaded the Unholy Cathedral!
He fled the Unholy Cathedral seeing no chance to win.
On level 18 he entered the Vaults.
He came, he saw, but he left.
On level 20 he was foolish enough to enter the Mortuary!
He managed to escape from the Mortuary!
He left level 22 as soon as possible.
On level 22 he entered the Lava Pits.
He decided it was too hot there.
Then at last he found Dis!
He nuked level 24!
On level 24 he finally sacrificed himself to kill the Mastermind.
-- Messages --------------------------------------------------
You enter the damned city of Dis... You advance to level 10! Press <Enter>...
Are you sure you want activate the thermonuclear bomb? [Y/n] You use a
thermonuclear bomb. Warning! Explosion in 10 seconds!
Warning! Explosion in 9 seconds!
Warning! Explosion in 8 seconds! There is a lever (woah!) here.
You pull the lever... Warning! Explosion in 7 seconds! There is a lever
(woah!) here.
You start running!
Warning! Explosion in 6 seconds!
Warning! Explosion in 5 seconds!
Warning! Explosion in 4 seconds!
Warning! Explosion in 3 seconds!
Warning! Explosion in 2 seconds!
Warning! Explosion in 1 seconds!
You feel relatively safe now. Congratulations! You defeated the Spider
Mastermind! Press <Enter>...
-- General ---------------------------------------------------
61 brave souls have ventured into Phobos:
50 of those were killed.
And 2 couldn't handle the stress and committed a stupid suicide.
9 souls destroyed the Mastermind...
1 sacrificed itself for the good of mankind.
8 killed the bitch and survived.
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