I finally managed to win too!
I didn't find the BFG, but I had shitloads of plasma ammo while the other ammotypes were slowly depleted... (note the multiple chainguns) I found a lot of red armors really early, but later on only one so I went through with damaged armor most of the time.
I beat him with some rocket shots that must have been lucky on the damage rolls and then after having teleported from a corner, healed and getting hit with a rocket I sniped at the out-of-range CyberDaemon (I was blown far back) with 2-3 plasma bursts which finished him off.
ALMOST 100%! I know the one I missed too, it was a hell knight camping in a corner and I didn't want to waste ammo on him...
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DoomRL (v.0.9.8 (WIN-S)) roguelike post-mortem character dump
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EvilP, level 7 soldier, defeated the Cyberdemon
on level 20 of the Phobos base.
He survived 88896 turns and scored 39785 points.
He killed 426 out of 427 hellspawn. (100%)
He was a real killing machine...
He found the Phobos Arena.
He stormed the Chained Court.
He fought on Hell's Arena.
He faced The Wall.
-- Statistics ------------------------------------------------
Health 39/50 Experience 33788/7
ToHit +3 ToDmg Ranged +0 ToDmg Melee +0
-- Traits ----------------------------------------------------
Hellrunner (Level 1)
Tough as nails (Level 3)
Eagle Eye (Level 1)
Cateye (Level 2)
-- Equipment -------------------------------------------------
[a] [ Armor ] red armor [2/4] (46%)
[ Weapon ] plasma rifle (1d8)x8 [8/40]
[c] [ Boots ] plasteel boots [8/8] (100%)
-- Inventory -------------------------------------------------
[a] blue armor [2/2] (96%)
blue armor [2/2] (100%)
[c] double shotgun (6d3)x2 [0/2]
[d] advanced rocket launcher (4d5) [1/1]
[e] chaingun (1d6)x5 [50/50]
[f] chaingun (1d6)x5 [50/50]
[g] plasma rifle (1d8)x8 [40/40]
[h] plasma rifle (1d8)x8 [40/40]
shotgun shell (x36)
[j] rocket (x3)
[k] rocket (x10)
[l] power cell (x20)
[m] power cell (x50)
[n] power cell (x50)
[p] thermonuclear bomb
-- Kills -----------------------------------------------------
77 former humans
46 former human sergeants
25 former human captains
31 imps
51 demons
47 lost souls
33 cacodemons
15 barons of hell
1 Cyberdemon
26 hell knights
20 arachnotrons
7 former human commanders
-- History ---------------------------------------------------
He started his journey on the suface of Phobos.
On level 2 he battled through a maze of rooms.
Afterwards he fought on Hell's Arena.
On level 3 he battled through a maze of rooms.
He then stormed the Chained Court.
On level 4 he battled through a maze of rooms.
On level 5 he found hellish caves.
On level 6 he found a hellish city.
On level 7 he found hellish caves.
Afterwards he witnessed the Wall.
On level 8 he battled through a maze of rooms.
On level 9 he battled through a maze of rooms.
On level 10 he found hellish caves.
On level 11 he battled through a maze of rooms.
On level 12 he battled through a maze of rooms.
On level 13 he battled through a maze of rooms.
On level 14 he battled through a maze of rooms.
On level 15 he found hellish caves.
On level 16 he battled through a maze of rooms.
On level 17 he battled through a maze of rooms.
On level 18 he found hellish caves.
On level 19 he found a hellish city.
Then at last he found the Phobos Arena.
There finally he defeated the Cyberdemon.
-- General ---------------------------------------------------
Before him 23 brave souls have ventured into Phobos:
20 of those were killed.
2 of those were killed by something unknown.
And 1 couldn't handle the stress and commited a stupid suicide.
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