Where can I find hireable Black Dragons? I've only found 2 eggs....

Also, where can I hire Arch Devils?

In the Land of the Dead, you will often find a bunch up in the mountains. Also, in the Magic Valley in Ellinia, the mage hiding behind the magic range will sometimes have some.

I'm just starting to experiment with Demons. I added some demonesses, but for some reason my inquisitors weren't able to resurrect them! Is this supposed to be the case? Is resurrect not supposed to work on them? If this is the case, are they worth getting, with all the morale hits and all?

In the beginning of the game I went for the usual strategy with 2 melee and 3 ranged units (playing as a Paladin) - Royal snakes + bears and inquisitors, archmages and archers behind them.

In the mid-game, I started to get a bit more range-oriented. Both types of elf archers, human Archers, Skeleton Archers and some horsemen to tank (rather poor tank, should have taken ents).

Now in the late game, I keep Knights, Demons and Arch demons as melee units and 4 types of archers. This allows for a lot of flexibility - from 4 ranged + a tank to 3 melee + 2 archers. Lets see how the final battle will go.

EDIT: As for the last battle, close-combat troops are essential. Knights with sweep are a battle-winner, especially if you manage to get them surrounded by dragons. Ogres hit like hell (gift is very useful here), and Demons give extra diversion. In my game I found ONLY 13 Archdemons... Pitiful. I still used skellies though. A full troop of skels with dragon arrows drops a troop of black dragons in 1 hit. They will also draw the attention of other dragons to them for 1-2 rounds, which is rather cool.

I hate that hypnosis spell Haas casts, though.

Resurrection doesn't work with Demons

Are they worth getting? Demons are great - lots of attack&defence, 3 speed, always retaliate (perfect combo with Reaper's Timeback). Imps - no retaliation and 2 charges of fire ball. Cerberuses - 3 head attack (in HoM&M they also had no retaliation, it's a pity). I didn't like Demonesses though, but fighting against them is annoying (Magic Shackles are essential)

I killed Baal and still cannot recruit Archdemons. Where do I find them?

Also, isn't the game pretty much over once you get Archdemons?

Does Sacrifice work on them?

I found them only in Baal's castle, after beating him. There were only 13 and that was all. I did a pretty thorough search of Demonis, the castles (I married Xeona, still nothing) and the buildings, as well as the labyrinth and the orcs' lands. That was it.

Maybe we're just unlucky. However, Archdemons aren't that wickedly powerful. You should keep them in reserve and use them only vs. dragons. Haas has high level hypnosis and he can possess pretty much any units that isn't mind immune.

Resurrection doesn't work on ALL Demons. However, Sacrifice still does. This way I managed to rise 90 Demons from 2 bought in tavern in Arlania ;)

Yes, I also used sacrifice to grow some nice big demon stacks. What do you mean it doesn't work on "ALL demons"? Does it work on some? If so, which ones? Or are you saying it doesn't work on any demon?

Hmmm, people keep saying that you can recruit them at Baal's castle, but I have not been able to find them. It's funny how you can only recruit 13 of them, however. It must be related to the fact that they have 666 hit points! :)

Thanks for the information on the Haas. I will definitely keep in mind.