The Fortress was both ancient and new; in the valley of Time-Stands-Still time was not. The sun froze at midday, for there was no night. The battlefields were strewn with freshly slain soldiers of two forgotten armies. Death hovered above the Fortress at Time’s End, and chuckled at the cosmic joke. The dead could not die, because to do so would be to advance in time a kitten’s breath, an instant – and, of course, that could not happen because time was frozen.
This is a direct continuation of Revenge of Balrog, so if you’ve arrived here without reading about that game, you should go there first.
The publisher Bob Lidill (of the Programmer’s Guild, who we’ve seen most of the library of now) also published tabletop roleplaying supplements under the name Rider Fantasy Creations. According to this interview, briefly in 1981 he “inadvertently” owned the character Grimtooth due to a paperwork mix-up. Grimtooth is familiar amongst tabletop-RPG aficionados as the fictional author of Grimtooth’s Traps.

The traps are not tied to any particular system so the books are still used by GMs who are hungry for blood and/or comedy.
Another one of the Programmer’s Guild games — Gauntlet of Death, by Charles Forsythe — was loosely based on Grimtooth. We’ve skipped over it because it isn’t really an adventure game, but here’s a screenshot anyway:

Top down view, you’re the “+” sign.
This is all pertinent for both Revenge of Balrog but especially its follow-up. Fortress at Times-End is trap-heavy in a classic dungeon crawl sort of way that makes me think Don and Freda Boner were also familiar with the ways of Grimtooth.

From The Captain 80 Book of Basic Adventures.
The game also has a bizarre opening where I was stuck for a good half-hour. You start outside the castle with a closed drawbridge, and the knife, hat, and sword from the previous game in your inventory.

A screenshot of frustration.
I was ready to start perusing source code when I realized I hadn’t tried the meta-commands “HELP” or “HINT”. Deciding I needed to see if there was in-game help first, I tried HELP, which opened the drawbridge.
We’ve had games where HELP/HINT give information that’s been essential (Bilingual Adventure and Alien Egg spring to mind) but this is what normally is a command to the computer with no in-game reference being delivered as sort of a magic word. (SAY HELP incidentally does nothing even though the verb SAY is understood.)
Not far in is a “portrait of Bnai T’ Loth, the Red Warlock of Death” followed by your hat vanishing and your sword turning into a “long pipe”.
The hat shows up not long after in a “hat rack”, followed by a chest of gold which is (of course) a trap.
Progress continues one-way into a wine cellar, and, oddly, a confrontation with the Balrog, who doesn’t do anything and I assume you’re supposed to just skip by.

FIGHT BALROG: “Try something else”
This is followed by yet another trap where the walls are closing in, and the game helpfully says you need to LEAVE an item behind to survive (it’s the long pipe that your sword magically turned into).
Immediately after there’s a very standard maze where all the rooms have helpfully been marked with various torture devices, with the catch that the maze is timed; you die after a set number of turns inside. This is one of the most uninteresting game timers I’ve run across, because there’s no way to “hurry it up” exploring — the connections are all random so there’s no strategic choices where you might suss out the right way to go, you just get lucky or you don’t.

For a timed event to have drama, I have to feel I have failed somehow if I missed the timer (like the ending of Domes of Kilgari). Here it’s more like I’m forced to roll two dice and get double-sixes in a set number of rolls — so what if I didn’t get lucky?
After the maze, I found a key and fumbled my way up to a small “second floor” area with a dining room, living room, library (the book case has a sword, for when a book deserves a really bad review), a dining room, a kitchen, and a breakfast room. The dining room is the most interesting place, but also a trap:
The table doesn’t otherwise react when you drop the wine bottle, and after that only EAT FEAST seems to work. Dropping the bottle anywhere other than the feast just causes the bottle to explode. Dropping the bottle at the feast, leaving, and coming back leads to no reaction that I can find (although I acknowledge I might need to play around with this more).
I’m not sure why I’m being resistant to hints on this one; I suppose the author-vs-player dynamic here is a little more pronounced and I want to win. Also, the bonus feeling of I got past the completely obscure opening, surely I can beat this one. So while my readers like to look in source code ahead of me, if you do, please leave any comments in ROT13; I’m going to keep hacking a bit longer.
From that river came Seerson — as had explorers and Adventurers before him — seeking the key that would unlock the Fortress, releasing the secrets contained within.
The Spirit-of-the-Sky hovered above the valley, as did Death, each waiting to see what would become of Seerson. These two cosmic entities eyed each other warily, while below Seerson tackled the puzzle.
The cosmic dice rolled once more…
Just a brief note here I managed to finish (I’ll post tomorrow) in case anyone was thinking of source-diving.
I completed the game as well last night after a source dive (which helped by giving me the recognized verb list). I’m quite sure there is one bug (gur Onyebt fubhyq *abg* nccrne va gur jvar pryyne, ohg engure va gur tnzr’f svany ybpngvba) but thankfully that seems to have cosmetic effect only. Looking forward to your post!
Ha, wow. I was wondering if the Balrog-invisible thing was intentional, it didn’t strike me at the time the literal Balrog object had just been placed in the wrong spot.
(I’m not sure if the bug is reproduced correctly from the printed book or got added after by a bad transcription.)
I remember Grimtooth, especially the iron maiden helmet! I think this is why I know what an iron maiden is. (As you may remember from Quondam.)
The thing I most vividly remember from Grimtooth is an extraordinarily elaborate trap in which every obviously fatal element cancels itself out–the cascading lava hits the flooding water and cools into ordinary rock, that sort of thing–but it appears this is not actually in Grimtooth. Hmm.
Maybe in one of the later volumes? There was a 1981 original (I checked and I don’t see the water one) but there were other Grimtooth books after.
Thinking it over the Grimtooth book was something one of my friends had, not me. The trap I’m thinking of was probably in a Dragon magazine or something.
this is what normally is a command to the computer with no in-game reference being delivered as sort of a magic word. (SAY HELP incidentally does nothing even though the verb SAY is understood.)
Weird. I wonder if, despite the lack of response to SAY HELP, we’re nevertheless meant to picture the character shouting “HELP” and being heard by someone inside?
This game sure is full of typos (“That’s beyond by power”, “Your heart is cut in halt“)
Looks like both of those are transcription errors.
https://archive.org/details/Captain80BasicAdventures/page/n63/mode/2up
The Balrog’s position is correct (i.e., he appears where you have the final confrontation, rather than the wine cellar) in the printed book scans you linked below.