The issue isn't limited to the tactical shotgun, or even assemblies. The same thing happened to me in a run after picking up the Necroarmor.
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DoomRL (v.0.9.9.3) roguelike post-mortem character dump
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David, level 2 Cyberdemon Lt. General, got too close to a cacodemon
on level 1 of the Phobos base.
He survived 278 turns and scored 6688 points.
He played for 55 seconds.
He opposed the Nightmare!
He killed 5 out of 39 hellspawn. (12%)
Who gave him the ticket to hell, anyway?
He was an Angel of Pacifism!
-- Special levels --------------------------------------------
Levels generated : 9
Levels visited : 0
Levels completed : 0
-- Awards ----------------------------------------------------
None
-- Graveyard -------------------------------------------------
################==####################===##################
#..#...#........==....................===..i.........#.....
#..#...#########==##########+#########===#############...^.
#..#...#.......==................i....===............#.....
#..#...#######==##############+#+####===##############.....
#..#...#.../...==...................h===h.i..........+.....
#..#...########==###############+####===##############.i...
#..#...+.......==...i...............===..............#i..hi
#..#...########==#########+#########===###############.i...
#..+...#.......==#..................===..i...........#.....
#..#...#.#######=#.................==h......##.......#.....
#..#...#.#..%O.#=#....0....##....i.===...##.##...i.^.#....h
#..#...#.#...O.#=#.........##...##.===...##..h....0..#0..i.
#..#...#.#.O.+.#=/.......0......##.==i..|...h........#.....
#..#...#.#.X...#=#...0.............=h=...............#.....
#..#...#.#....O#=#................===......##.##.....#.....
#..#...#.#.+...#=#..+....##....h..===.0....##.##...0.#.....
#..#...#.###/###=#.......##.......===................#.....
#..#.}.#.......==#................===................#....^
###############==##################===#####################
-- Statistics ------------------------------------------------
Health 0/60 Experience 672/2
ToHit Ranged +0 ToHit Melee +0 ToDmg Ranged +0 ToDmg Melee +0
-- Traits ----------------------------------------------------
Ironman (Level 1)
Hellrunner (Level 1)
HR->Iro->
-- Equipment -------------------------------------------------
[a] [ Armor ] nothing
[b] [ Weapon ] nothing
[c] [ Boots ] nothing
[d] [ Prepared ] nothing
-- Inventory -------------------------------------------------
[a] Necroarmor [6/6] (100%)
[b] large med-pack
[c] large med-pack
[d] large med-pack
[e] thermonuclear bomb
-- Kills -----------------------------------------------------
1 lost soul
4 cacodemons
-- History ---------------------------------------------------
On level 1 he finally was killed by a cacodemon.
-- Messages --------------------------------------------------
are hit! The cacodemon fires! You dodge! The missile hits the
cacodemon. The cacodemon fires! You dodge! The missile hits the cacodemon.
Your blue armor is damaged! The cacodemon dies.
You start running!
The cacodemon fires! You dodge! The missile hits the cacodemon. The
cacodemon dies. You advance to level 2! Press <Enter>... The
cacodemon fires! You dodge! Boom! The cacodemon hits you. The cacodemon
hits you.
There is a Necroarmor [6/6] (100%) lying here.
Unknown command. Press "?" for help. There is a Necroarmor [6/6] (100%)
lying here.
You picked up a Necroarmor [6/6] (100%). The cacodemon fires! You are hit!
The cacodemon hits you. The cacodemon fires! Boom! The cacodemon
fires! You dodge! The missile hits the cacodemon. The cacodemon dies. The
cacodemon hits you. Your blue armor is completely destroyed!
You die!... Press <Enter>...
-- General ---------------------------------------------------
Before him 1663 brave souls have ventured into Phobos:
1390 of those were killed.
4 of those were killed by something unknown.
112 didn't read the thermonuclear bomb manual.
And 51 couldn't handle the stress and committed a stupid suicide.
Some rumours though, say that the Cyberdemon was killed already!
Is he immortal? 106 souls claim to have killed him...
24 sacrificed itself for the good of mankind.
72 killed the bastard and survived.
10 showed that it can outsmart hell itself.
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