rakovsky: is the myth of lonely knight, testing his value and to seek the grail efficiently you must not be in group but sparse (and I advise to do it even when you gain more heroes: there are a lot coming by fullfilling missions or just encountering by scouting the land). You choose the pop you want depending the dificulty you want but normaly is just regular 75 for aoe2 first scenarios. Anyway they are limited well by buildings, don't worry. Ennemies dont have villagers to build more houses (you don't want 200 knights or archers (=instant kill) on Arthur no?). In that regard, the enemies always grow in number when you go deeper in the land: it is progressive like a role playing game. Some tricks block enemies to group too much (dont use recent ai but original).

What population should you pick? 200?
I haven't read the various Arthurian legends. I don't understand why Arthur would go alone instead of joining his knights.

NEW UPDATE (version 12):
New secondary quest: "The Purple Knight"
I added also an elite mangudai, a heavy cavalry archer and a heavy camel in the second courtyard of Mordred fortress.
Enjoy!

NEW UPDATE (version8):
New secondary quest: rescue Joan the Maid.

NEW UPDATE (version 7):
One new secondary mission and location: "The Accursed Monastery".
Dedicated to all Diablo fans.

NEW UPDATE (version 6):
Lot of improvements of any kind.
Enjoy!

New update (version 5):
I boosted attack and HP of ferocious animals to make them more dangerous, even for heroes (now, when in band, they can kill a hero, even Arthur, making the game more chalenging).
Now you can no more cheat with Bors as vil to build by collect and cut wood to go out.
I changed some names (like Merlin instead of monk) and added some dialogs and views changed here and there and an accursed tower in the ruins of the spectre.
Merlin got also +100 HP until he carries the relic (which makes him back to a normal monk).

I didn't remember that there is also a ram, a scorpion and an engineer (bombard cannon) to obtain.
Good luck (not easy even for me but excellent and progressive micro management training and understanding)!
You can have pretty all tech at the end improving all heroes fully. The final riddle is not so easy to understand.

I said it: Morgan's fortress (it's behind Mordred Fortress, so if you didn't go in, you can't have found him).
Did you find the trebuchet and Perceval now?

I did not understand where it was Merlin

Last thing: if you click on signs, they give you geographical infos.
Scout all the map meticulously, that's the hint i gave in the scen (trees often masks some paths in the forest, you already knows it and it is realistic).

no what? of course yes. I wont explain all. Find them. Do you really think i didnt test my own scens? Scout better and follow the first advice i sent in comment.
Merlin appears only at the end (he's emprisoned in Morgan's fortress).
I wont reveal all here to spoil my own scen (come on!).

8: Merlin (a monk, the only unit who can bring the Holy Grail (relic) in the castle of Camelot)

7: a trebuchet with throwing axemen.

Perceval (first a skirmisher and after a Frankish paladin (hero, so he heals himself))

these no

LOL! funny no the forest trick (they are many of that kind)?
For info for all the secondary quests can give you:
1: Bors (a hussar: he can scout without being attacked by wolves)
2: Perceval (first a skirmisher and after a quest a Frankish paladin (hero, so he heals himself))
3: Lord Caradoc (a teutonic knight)
4: Lancelot (aoe2 regular hero)
5: Gawain (same)
6: a pagan magician ( monk you mentioned in Camelot, accross the river)
7: a trebuchet with throwing axemen.
8: Merlin (a monk, the only unit who can bring the Holy Grail (relic) in the castle of Camelot)
9: some transport ships to cross some rivers
10: a villager with cart (tradecart) who can spy neutral player for you.
Voilà!

how can I take the grail?

2 HEROES + 1 Young knight (the road is very difficult to find)

example of norman's barbican at Caen (France): https://fr.wikipedia.org/wiki/Barbacane#/media/File:Caen_DSC0974EC.jpg

[STW italia] Markus C.
A simple question: what heroes did you find and what upgrades you found (they are many, it's above all a scenario based on 1 main mission, but tens of secondary missions like an open role playing game: many ways and many paths for the same result to symbolize the freedom of real world, the profound meaning of the quest of the grail being to follow the quest to grow, not obligatorily fulfill: it's an initiation)?
Thank you for interest.

Hi Markus.
Lot of missions are optional. The main mission is to take the relic in your monastery symbolizing the grail, so its quite obvious (you dont have to destroy blue).
Destroy the gate of south blue fortress and let's see what's happen.
Why are they so resistant in the north? Its the main fort so it should be. It's just a barbican, typical Anglo-French medieval castle defensive architecture (fortified gate with two towers in front of the main gate of the fortress and linked to him by a wall or an arch or a bridge crossing the moat like here).
Do the first mission here and you will see it can become easy in fact. Use a hero to hit the gate and another to avoid arrows with patrol perpendicular to the arrows direction (would be easier with heavy cavalry).
He said himself, the wizzard cant go out (the river prevents it), he's disinterest of the grail because celtic pagan, not christian. You can lure to him units to convert but it's hard and not an obligation.
Voilà!

Sorry I'm having problems:

1) Should I destroy the fort in the lower right corner before going north to the great fortress?

2) Why are the gates so resistant (of the blue fortress to the north)?

3) Can I use the wizard in Camelot?