A good practice i found to get rid of the small amount of rockets in inventory is to fight in Hell's Arena and become champion.
At least in lower level of difficulty tough. As the monster apparently becomes even more dangerous in higher difficulty level, Hell's Arena may be too difficult depending on what you have found in regular levels.
Once you have won, there's a bunch of rockets that spawn, and even more interesting there's a rocket launcher that appear too.
So winning an early Hell's Arena can give you a rocket launcher and lots of rockets early in the game.
It makes a huge difference i found.
It is recommended to have found the combat shotgun before entering Hell's Arena, you really need the extra shots it allows for the last round with the cacodemon.
Oh and YES !
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DoomRL (v.0.9.9.1) roguelike post-mortem character dump
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Huio, level 9 Demon Corporal, defeated the Cyberdemon
on level 25 of the Phobos base.
He survived 111012 turns and scored 41869 points.
He played for 1 hour, 30 minutes and 9 seconds.
He was too young to die!
He killed 336 out of 378 hellspawn. (88%)
-- Awards ----------------------------------------------------
Hell Champion Medal
Arena Bronze Badge
Scavenger Bronze Badge
UAC Bronze Badge
-- Graveyard -------------------------------------------------
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-- Statistics ------------------------------------------------
Health 50/50 Experience 37907/9
ToHit Ranged +0 ToHit Melee +0 ToDmg Ranged +2 ToDmg Melee +2
-- Traits ----------------------------------------------------
Finesse (Level 2)
Son of a bitch (Level 2)
Whizkid (Level 2)
Triggerhappy (Level 2)
Ammochain (Level 1)
SoB->SoB->TH->Fin->Fin->WK->MAc->WK->TH->
-- Equipment -------------------------------------------------
[a] [ Armor ] modified onyx armor [2] (BT)
[b] [ Weapon ] plasma rifle (1d7)x6 [40/40]
[c] [ Boots ] modified protective boots [2/2] (192%) (AB)
[d] [ Prepared ] double shotgun (8d3)x3 [0/2]
-- Inventory -------------------------------------------------
[a] rocket launcher (6d6) [1/1]
[b] modified chaingun (1d8)x4 [40/40] (P2)
[c] Malek's Armor [3/3] (100%)
[d] Butcher's Cleaver (5d6)
[e] 10mm ammo (x100)
[f] shotgun shell (x50)
[g] rocket (x10)
[h] rocket (x10)
[i] rocket (x10)
[j] power cell (x50)
[k] homing phase device
[l] envirosuit pack
[m] thermonuclear bomb
[n] thermonuclear bomb
-- Kills -----------------------------------------------------
62 former humans
34 former sergeants
15 former captains
67 imps
29 demons
55 lost souls
22 cacodemons
7 barons of hell
1 Cyberdemon
7 hell knights
11 arachnotrons
7 former commandos
1 pain elemental
3 arch-viles
1 mancubus
12 revenants
2 bruiser brothers
-- History ---------------------------------------------------
He started his journey on the surface of Phobos.
On level 2 he entered Hell's Arena.
He left the Arena as a champion!
On level 4 he found the Butcher's Cleaver!
On level 5 he stormed the Chained Court.
On level 9 he found Hell's Armory.
On level 15 he encoutered the Phobos Hellgate.
On level 20 he entered the Vaults.
He came, he saw, but he left.
On level 24 he found the Malek's Armor!
Then at last he found Phobos Arena!
On level 25 he finally defeated the Cyberdemon.
-- Messages --------------------------------------------------
Fire -- Choose target...
Fire -- Choose target...
Fire -- Choose target...
Fire -- Choose target...
Fire -- Choose target...
Fire -- Choose target...
Fire -- Choose target...
Fire -- Choose target...
Fire -- Choose target... The missile hits the Cyberdemon. The missile
hits the Cyberdemon. The missile hits the Cyberdemon. The missile
hits the Cyberdemon.
The Cyberdemon fires! You dodge! Boom!
The Cyberdemon reloads his rocket launcher.
Fire -- Choose target... The missile hits the Cyberdemon. The Cyberdemon
dies. You feel relatively safe now. Congratulations! You defeated
-- General ---------------------------------------------------
Before him 61 brave souls have ventured into Phobos:
47 of those were killed.
1 of those was killed by something unknown.
2 didn't read the thermonuclear bomb manual.
And 10 couldn't handle the stress and committed a stupid suicide.
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So happy.
And it unlocked 2 more challenges apparently, as i won then enough badges to reach Demon - Corporal rank.
Getting good weapon early makes a big difference, the combat shotgun then the chaingun managed to get me through nearly everything.
Of course the traits helped a very lot, increasing damage, rapid fire and infinite ammo strongly help with the 2 power mod i added to my chaingun too.
Nothing against your win, but why the fuck would you use a bulk mod on a piece of armor with infinite durability? It does nothing but waste a mod slot and a bulk mod. For Onyx armor, use a power mod instead.
For the wall: basically, what Duke said: Blast away a hole in either near-top or near-bottom, park at a corner with a shotgun, apply liberally. Hell, you can even blind-fire around a corner and if you hear screams, repeat. Just don't do it with a rocket launcher, because if you miss too many times you might blow up the goodies.
For the Hellgate: Upon getting there, I pick up the armor and medkits, and then what I do is use the health globes as a buffer (over 100%) and then tab-run away from the lost souls back to the door with either double shotgun or combat shotgun, then I park one space behind the door and close the door every time i reload. The Cacodemons on higher levels will kill the lost souls in groups.
Alternatively, if you have a double shotgun with the Shottyman skill, you can run once till they bunch up, shoot a group of them (the spread should hit at least three at once and kill them), move another space, shoot again, then run back to the door.
Or if you've already done the Halls of Carnage, use your BFG.