I played this game again and found a strategy, which I never read elsewhere.
My goal was to eliminate all of Doomdarks forces as soon as possible with all the 28 charaters alive.
There is an article to do this by defending Xajorkith in more than 80 days.
I did in 40 days. The keypoint of the stategy is holding Doomdark at the keep of Blood.
Doing this only a few armies of Doomdarks forces will reach the southside of the map.
You will have to stop them, that wander the westside of the map at Gard later in the game.
To stop Doomdark at the keep of Blood you will have to recruit very effectively and all the given suggestions of routes seem wrong to me.
Then do three things:

1. Reinforce keep of blood with big force (five lords at day 4 and then many more)
2. Conrol citadels of Marakith and Kumar with one or two lords to stop armies that want to go south.
3. Start a offensive north (Dream, Ithrorn, Herath, Whispers) very early to occupy keeps, this makes Doomdark even more "unhappy" and wont have to take them later.

This strategy is strong an makes fun, because it feels like a real battle game.
If you´re recruiting clever you will get Lord of Gard at day 1, Lord of Herath at day 3 and Lord of Ithrorn and Dregrim at Day 4 to start the northern offensive.
Get the Lords to the south at last (Thimrath, Rorath, Xajorkith), because the routes there are very bad and concentrate on the ones near the battlefield.
Perfect routes to maximise the effects of the cup of dreams are the key feature.

Yeah, holding the Keep of Blood is probably the hardest and one of the most offensive strategies. I never used Herath on the offensive, though, since it's hard to hold the Marakith - Herath - Kumar line.

Normally I yield Keep of Blood, and try to hold the line from the Keep of Dodrak - Keep of the Moon - Citadel of Shimeril instead.

Once I retreated all my lords to Citadel of Xajorkith, and IIRC I figured Doomdark had about 50,000 troops.

One thing that also affects Doomdark's movements, is where you send Luxor. I think Doomdark had about 10,000 Riders that are set to pursue Luxor, so if you send Luxor south to Gard, it will put more pressure on Dodrak and Blood.

Luxor only gets Lord of Thrall in my game and then heads to Keep of Blood, because I want Doomdarks forces to go there, and he will influence the ice fear and help his forces.

Herath is the guy, who reaches Ithrorn at first and Ithrorn can recruite Lord of dreams, thats important.

Where do you send the other guys? I assume you send Corleth to recruit Shadows, Kor and Dreams?
Morkin south where he's safe?
And Rorthron east via Shimeril?

I usually send Morkin north to Shadows, Farflame, Lothortil and Gloom myself.
Luxor south, and Rorthron east.

Corleth gets Lord of gard at day 1, he is the only one to do that and then goes to Kor - Gloom to help Morkin.
Very much use of cup of dreams.
Rorthron is the second user of the cup of dreams.
Find the route Shimeril - Marakith - Athoril - Dregrim
He will reach Dreegrim at day 4 and then go south Trorn, Xajorkith, Thimrath, Rorath
Morkins way is standard stuff.

@ OP. That's roughly how a beat it years back, playing on a ZX spectrum. :)

Before I could do this I had to make a map, square by square on graph paper.

The start of the game:
Day 1: Luxor E to Blood, Morkin meets Shadows, Rorthron E to Shimeril, Corleth S to Gard (2x Cup of dreams) and then way back, Shadows kills Wolves that will be in Morkins way and heads to Keep of blood then, Gard heads to Brith (1x cup of dreams)
Day 2: Luxor meets Blood and heads to Thrall, Morkin N to Farflame, Corleth heads to Tower of Dodrak (cup at Gardhenge), Gard meets Brith and heads to Mitharg, Brith goes to Keep of blood via keep of the moon.
Day 3: Rorthrons big journey - he reaches Shimeril taking three cup of dreams to Marakith and again two cups to Athoril - there you should make one step to reach Dregrim the next day, Marakith reaches Herath the same day and Herath heads to Ithrorn (cup of dreams), Athoril going to Dawn, Gard reaches Mitharg- Shimeril, Gard, Mitharg go to keep of blood
Day 4: Luxor meets Thrall - both going to keep of blood, Morkin reaches Farflame and starting to Lothoril, Corleth taking another cup on the way to Korinel, who might get attacked at this night, before Corleth reaches him the next day, Farmlame can assist Korinel the next one or two nights before going to Keep of blood, Rorthron reaches Dregrim and has completed his most important part, he can go to the south then (Trorn, Xajorkith, Thimrath, Rorath - all heading to keep of blood except Rorath), Athoril meets Dawn, who gets Morning the same day - all go to Keep of blood, Dregrim heads Utarg - Kumar - Whispers, Ithrorn will go to Dreams.
Herath rests a little at Ithrorn awaiting Whispers building a team like Dream/Ithrorn defending keeps against Doomdark and occupying new ones. Later they will meet and form a bigger team with Korinel, too and takie all the keeps in this area. Utarg and Marakith will defend at Marakith and Kumar at Kumar, but due to the northern fey attack there will be not much to do. Dregrim can join the northern attack after reaching whispers or stepping back to the west (Marakith). When the fey group controls the area the north and the attack at keep of blood decreases the Marakith group can head towards keep of blood taking back the keeps north of thrall.
Now you will have to defend a little against troops that will go south in the west. Defending troops at Keep of moon keep of torkren and keep of gard are nice and Rorath coming from the south will be helpful. He will stay there, because the battle of blood will be over at this point and you can go in the offensive against Valethor..
At the end of the game you will have lost only very few armies.

Seems you have worked out pretty much the optimal recruiting strategy.
The only downside is that you'll probably reach Korinel too late. For this reason I send Corleth north at once, recruiting Blood on the way, I think (or else Rorthron does), and send Luxor south to Gard,

The problem with Korinel isn´t that big, I think.
I mentioned the wolves, Shadows kills at day one east of the ruins in Morkin´s way, because that will help Korinel, as Morkin will reach Farflame at the right time. If Korinel gets attacked at that night with the help of Farflame, its not too bad, because Doomdark will suffer a lot.
I like Luxor going to Thrall, because nobody else can go there very well and Luxor stays near Keep of blood all the time and Corleth has too much time at the end, not knowing what to do after he reaches Gloom and no need to go to dreams.

The Blood Defence is particularly hard, but not as hard as the Gorgrath Gambit... :)

Please, tell me about it, because I dont´t know what it is.
The Blood Defense doesn´t seem hard to me but I´m interested in a challenge.

Edit: I set my record completely eliminating Doomdark to 29 days with the blood defence and don´t think that I can improve much. Now I tried to deploy as much lords at the keep of blood as were needed. Others refreshed at the keeps behind. The offensive at the ending was faster then and the coordination with the two other groups was better
So I will take a look at DDR now. I have never played it, but doubt if I will like it the same.

Thank you for the answer.
I don´t know if I played like that, but the fastest way to attack Gorgorath seems to me to defend keep of blood for a while and when you have defended against the big luxor attack you can go to Gorgorath (day 10-15). I had tried to atack the keeps of valethor imediately, but this really felt like a gambit, because losses were (too) huge. Maybe I will test again, to see if it´s playable.
Defending keep of dodrak seems bad to me, you have to split up forces, distances getting longer and the keep is only of small strategic value.
Sending Corleth to the north immediately is bad, I think. Movement of doomdarks armies also makes it better first going to gard, cleary the best strategy.
I tried to win the game as early as possible on a military way. First I tried sending Corleth to the north, but again it was worse. Going to gard and then back to kor again was the solution.
I captured Ushgarak at the 11th day, it took me two nights to win the final battle. I allready managed to win in one night at day 13, so maybe winning at day 10 might be the ultimate record.
What to do with luxor is the most interesting question in these games.

Edit: I did it. Ushgarak fell at day10. Who can beat it?

Amazing... I've heard rumour of a Day 9 Victory, but it's only rumour...

Back when I played this game more seriously, I won a military victory on Day 9. I still have the day-by-day savegames:
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