Walkthroughs for custom maps.

I am attaching the archive with the map.
The map has also been added to maps4heroes: http://www.maps4heroes.com/heroes3/maps.php?keywords=Astral+Venice&type=&size=&difficulty=&sort=3
Map screenshots and texts can be seen here: http://www.fatalgame.com/download/maps/heroes3-map-astral-venice.html (registration is required for downloading, and it lacks the author's description found in the archive)

So, this is a lesser-known and less popular map by the author of the recognized hit "The Fall of Atlantis" (hereafter abbreviated as "TFoA").
Map Language: English.
Genre: RPG.
Plot: While aristocratic factions squabble over fabulous wealth of the Most Serene City, evil conspirators plot the overthrow of the Republic. Beware the clandestine Council of Ten (blue), treacherous Papal forces (red) and the Genoese lodge (teal)!
Thus, we find ourselves in the center of a brutal medieval struggle between clans.
You can play as one of 4 sides (races): Brown (Conflux), Green (Rampart), Orange (Inferno), and Purple (Necropolis). The most powerful opponents (AI players only) are Red, Blue, and Teal. Our main enemy is Red; his primary hero is Pope John XXIII himself.
This map is not for the faint of heart: enemies here do not sit still, but actively and aggressively explore the world, and they are not "punching bags"—on the contrary, for a while, you will be the "punching bag" for them! I would like to draw the attention of strong players to this map: before you is pure hardcore, and not the modern kind using convoluted tricks and game bugs, but completely classic (the map was made in 2001).
Overall, unlike "TFoA", this map doesn't even try to give us the illusion of "symmetry" regarding player capabilities and starting positions (the author's probable motto: "Balance? What balance?"). Choosing a race here requires even more thought than in that case. Also, the topography of the map is much more confusing than in "TFoA": this is contributed to by numerous monoliths with exits in various places, whirlpools, and narrow canals with plenty of obstacles.
Common to both maps are regular events that take away resources and ambushes in certain locations (fortunately, there are noticeably fewer of them here). Also, some artifacts have hidden guards. On the other hand, an unknown benefactor periodically sends us resources. And things are easier with them here than there, where we only have enough gold toward the finale.
User Mn from the now-defunct gameforums.ru site (where I learned about it and downloaded it) gave a very insightful brief characteristic of the map:

All 4 playable sides start with extremely weak armies and are forced to fight their way through strong monsters. Computer players are very strong, but initially blocked by keymaster tents and other barriers. Over time, the probability of their attacks will increase and it will be very hard to fend them off, so you must develop as quickly as possible. Each playable side has its own development plot. I completed it only as Rampart, and got considerable pleasure. The map has everything: seer huts, keymaster tents, monster dwellings, including all types of dragons, and all types of artifacts. However, strong artifacts come at a high price: for example, for angel wings, you must destroy 4000 archangels. You can free many heroes with substantial armies from prisons. It is also good that the most powerful enemies stay put or are locked in a specific territory; they can be reached at any convenient time.

Here is another useful excerpt from the author's description:

Every playable fraction has some special advantage: for instance, Conflux is extremely dependent on the sea power and resources in the beginning, Necropolis has lots of refugee camps, etc. Use them wisely! Navigation is extremely important, as well as the external dwellings (especially those of dragons!). Water walk, Fly and Dimension Door are banned, and can be obtained only in special locations.

In my opinion, the best starting position belongs to Brown, slightly worse to Green, and the situation for Orange and Purple is quite dismal. Brown lives on an island where a shipyard can be built right in the city, and from there, via a whirlpool, one can sail almost anywhere (without fighting hydras!). The University of Magic allows learning the necessary schools of magic without relying on luck. Nearby is a second Conflux, as well as red, green, light blue, black, and blue tents, and if we remember the doubled phoenix growth... So, let the masters, the obsessed, or the masochists play the other races. At the same time, I admit that masters could complete it as any side (as confirmed for "TFoA"), but the strain of effort would be incomparable compared to playing as Conflux. However, it has its own difficulties: there is no fort in the city; you need to save resources to erect it, and only then build dwellings. Also, elementals cannot be resurrected.

Ability to choose the side to play.
High density of objects, artifacts, and monsters.
No strict linearity in progression: after getting out to "open water," we have great freedom of action.
No overpowered "unkillable" enemies and no need to spend long periods thinking intensely about how to defeat each of them: if you can develop successfully, perhaps only Councillor 9 (but killing him isn't mandatory) and, of course, John XXIII might trouble you among all enemy heroes.
Most of the tasks from seers and gatekeepers are optional.
There is almost no plot text, so no time needs to be spent comprehending or translating it.

General chaos of the map's topography. If I can still draw the approximate scheme of zones for "TFoA" after years, I would struggle to recall the "AV" scheme after just a month.
Huge imbalance in terms of vastly different starting conditions for the 4 sides, one of which must be chosen. In reality, the map seems "tailored" for completion by Brown; the other 3 possible races feel like an afterthought.
Banning the Summon Ship spell is overkill. I guess this was done to complicate the game, but such a decision creates a risk of getting into an unpleasant situation if you disembark from a boat on an island where there is neither a shipyard nor another boat, and your boat is accidentally summoned by another of your heroes or an enemy. It will be especially frustrating if you haven't learned Town Portal yet. Three weak enemy heroes ended up in such a situation in my game.
The Wizard's Hat, guarded poorly (by a random number of liches) and featuring a bunch of border gates that aren't actually necessary to pass through. Its accessibility radically eases the game if you take it, and conversely, radically complicates it if it falls to the enemy (as happened to me). It would be desirable to add obstacles so that the Hat could only be reached through all the southern gates (the author probably intended this but overlooked it), set a specific number of guarding monsters (better replacing liches with death knights or ghost dragons), and make it so that Flight or Dimension Door could only be obtained closer to the finale or excluded entirely. After all, it turns out that many obstacles and guards carefully placed by the author can simply be flown over (specifically, one can reach the pope either through winding underground passages with many border guards, or through an anti-magic garrison with legions of the strongest dragons and a gatekeeper, or simply jump to that city). In "TFoA", one had to sweat quite a bit to get the ability to fly!
There are 4 heroes named Luca Brazzi on the map (in prisons)—it's a bit confusing, and if you need to explain to someone else which Luca you mean, you'll have to use many words. However, the author did this intentionally: a rumor in the tavern confirms this.

Luca Brazzi has more than one face! Or there is more than one Luca Brazzi!

There are also redundant duplicate objects: in one place 9 green monoliths instead of one, in another—3 whirlpools instead of one. And some border gates serve a purely decorative function.

The spells Summon Ship, Dimension Door, Fly, and Water Walk are banned on the map (and cannot be learned by ordinary means).
Among artifacts, Angel Wings, Tome of Air Magic, Tome of Water Magic, Wizard's Hat, and Admiral's Hat are banned. The Wizard's Hat, which is the fastest and easiest to obtain, is located in cell 143,67.
The land cartographer is in cell 105,116.
The Necklace of Sea Guidance is in cell 14,134 with Orange.

First and foremost for a successful run: the correct choice of side. Here I'll use phrases from a famous joke: if you want "just sex"—play as Brown; if you need "hardcore BDSM sex"—try playing as Green, Orange, or Purple. ;)
Since players continue to make such a mistake, I'll mention this too: complete the map in "pure" SoD ("The Shadow of Death" or "Complete Collection"), but not in WoG, HoTA, or any other flashy mod! Otherwise, you likely won't be able to finish it at all or will constantly ask questions like this (video):

Strangely enough, in the map editor, it shows the red dragon stack to have 2 dragons only. In my game it appears to have lots of them... maybe because of wogifying?

Yes, buddy, you're a titan of thought: that's exactly why! :D Next, ask why you have a WoG-style Zmey dwelling instead of a dwarf treasury, a dragon cave instead of a Marlette tower, fires instead of wizards, and mithril lying on the ground, and that's just a small piece of the map!
Save the game regularly and often! I had to replay 1-3 days more than once.
Be prepared for the fact that on any given day, enemy actions will thwart any of your plans.
There are no safe places! From the moment enemies start roaming everywhere, you are in constant danger. Therefore, it is necessary to always move forward, conduct reconnaissance, capture new cities, and be ready to flee if there is somewhere to go. The most valuable thing you have is your main hero (or heroine), their troops, and artifacts. Everything else will have to be yielded to enemies if necessary. Only closer to the finale will you have the opportunity to settle scores with them and recover what was lost.
As in "TFoA", there are 3 key vital things here: Resurrection, Town Portal, and access to "open water." But with the 3rd, everything is very different: not every player will manage to sail freely immediately, but rather very late. Following those are 2 more vital things: Summon Ship and Captain's Hat. Obtaining them will significantly ease movement across the map. And by assembling the Admiral's Hat, you will be able to suddenly appear and disappear, snatching something from under the enemies' noses—an invaluable capability in guerrilla warfare! As you will soon see, the enemies' advantage is not only in the strength and number of their army, but also in the fact that they have Summon Ship, and some even have water walking (spell or artifact—I don't know yet). You also need to find the location of keymaster tents and visit them. Then you need to find where the artifacts that grant flight are located (you need to obtain Fly or Dimension Door, as some enemy cities cannot be reached without them, and victory conditions are standard). It is extremely important to try to take them before the enemies. It is most convenient to first take the Sphere of Vulnerability, and then with it, the Wizard's Hat or Tome of Air Magic.
Another important question: where and how to get troops? Ordinary accumulation in your own cities can be interrupted by an enemy capturing cities on any day. Therefore, you need to free heroes from prisons: they have fairly large armies. If you have the chance, hire a necromancer hero, level up Sorcery, and assemble the Cloak of the Undead King: with such an amount of "meat," assembling legions of liches will be easy. And then the map will become a "piece of cake," as the English say. But before that, you'll have to strain yourself considerably.
Also, check the tavern constantly: the HD-mod will allow you to conveniently "dig up" defeated enemy heroes with skills useful to you.
And the further you go, the more important it becomes to regularly give all "extra" artifacts to secondary heroes: my backpack filled up about 4 times, and sometimes I had to rush back urgently so the main hero could "change for the night."

I wanted to play as elves (Green), and that turned out not to be the best choice. Fortunately, I still managed to complete it.
The main heroine is the ranger Anna Foscari specializing in snipers—perhaps this is the only bonus the author gave the Green player. She also initially has all the necessary secondary skills (hello "007 chases Dr No" with its "guessing games" and "lotteries").
At first, I had to linger for a long time near my home Rampart, where there is almost nothing and nothing to do, but ahead was a formidable obstacle: chaos hydras, and I couldn't beat them without serious losses. Waiting and accumulating troops is possible, but not for long: the number of hydras also increases weekly.
Next, passing through the blue two-way monolith, I successfully freed Luca Brazzi from prison with a very decent army. Anna took his detachments for herself and used them as her main forces for a long time.
The second Rampart I captured was taken from me by Blue the next day.
Generally, about 3 times I really wanted to quit (when enemies captured my home Rampart and I had only 2 cities of other races left, then—when I saw that Teal took the Wizard's Hat and was using Dimension Door), but I persisted nonetheless, and not in vain.
A successful decision was passing through a one-way monolith north to Blue's Tower, Council Palace: I captured the city, beat Councillor 7 who was running nearby, and transferred two secondary heroes to this Tower. Thanks to veils of darkness, this area remained safe for a long time (until the very end of the game). True, there were tense moments with sudden enemy landings, but the first time the enemy, having captured the lumber mills, immediately retreated, and the second time a reload helped avoid the problem, and later I dug holes on the shore so the enemy couldn't disembark from the boat.
Capturing the Conflux Villa Capella gave me access to "open water" and the long-awaited freedom of action.
I didn't have to search for the Captain's Hat: I obtained it by beating one female enemy.
On 5-4-4 Orange disappeared, and the next day – Brown. This was my doing.
In the 6th month, I managed to dig up in the tavern the female enemy Councillor 7 whom I had beaten previously, with excellent skills and artifacts (including the Cloak of the Undead King). She didn't become the leading commander, but greatly helped in transferring troops and spells.
A bit later I beat di Stefano and was also able to dig him up in the tavern. He had the Sorcery skill! After supplying him with artifacts, he became stronger than Anna, and I appointed him as the main warrior hero. I sent him to raise liches, in which he soon succeeded. That's how I started to get back on my feet.
Since I have a Tower, I dug up a Dragon in the tavern and turned mages into wizards. And after capturing Castles, crossbowmen became snipers, and monks became wizards.
On 7-3-4 I beat the last weak hero of Teal, and Teal disappeared.
On 7-4-4 Purple disappeared from the map. On the same day, Anna beat 2 of Blue's heroes, and Blue also disappeared from the map.
Exactly on 8-1-1 (not on purpose) I beat John XXIII and captured the Castle Avignon. Immediately I was congratulated on victory.
Result: 197 days, 494 points. The Grail was dug up and installed, all cities, including neutral ones, were captured.
By the way, the Grail part was interesting: Teal figured out roughly where it lay and started digging. He made 6 holes, and then I interfered. And it turned out that the next hole gave the Grail!
Summary: although the map is not perfect, I received a lot of vivid emotions and pleasure during the walkthrough. The most impressive was the power of a multi-thousand army of liches. Moreover, although for the last two battles I was forced to combine all liches into one stack, the numerical overflow I feared did not occur. And there were 117329 (one hundred seventeen thousand three hundred twenty-nine) of them!
I will recommend placing the map in the largest online collections.
If you undertake to complete the map, and especially as one of the other 3 sides, write: what did you achieve?