In mission 3, we fought opponents 4 times stronger than us. Mission 4 the campaign finale (there are only four missions per campaign in Heroes6) takes challenge up a whole notch. Your only enemy, the Inferno faction, owns 9 towns and 4 forts, and they will keep coming at you even if you wipe out their army again and again.
Nonetheless, that's not where the main challenge of the mission lies. A few towns are garrisoned by some ridiculously large army, so large that they could eclipse the climax of the final boss battle. If you match that army to fight the final boss, they might actually win! Your objectives - take or destroy everything! It sounds really overwhelming.
But there are hopes - lots of hopes. Heroes6 campaigns are scripted in a way that you can frequently be crushed by scripted armies that are simply too large for now. However, these scripted armies do not grow at any noticeable rate! Your overall success is dependent on how many Inferno Forts and Towns you can bring down with a small starting army before you eventually run into a red-hot corpse incinerator. When that happens, you have to rely on your superior unit production to eventually bring you a deadly cold meat grinder yourself to take down the toughest Inferno towns.
There are two types of Inferno towns and forts: those on the surface and those underground. Those on the surface, once conquered, can be converted to Necropolis for your own benefit. Those below the surface, however, will be instantly demolished and their respective area is permanently sealed off. Your hero will be teleported back to the surface as well.
Since battles in this game usually involve stacks that can do 4 digits, if not 5 digits of damage each hit, it is a good idea to invest ability points into the passive combat category, after getting all the core abilities suggested in Mission 1 walkthrough. You should also try to raise your Magic Attack stat as much as possible, since your two most powerful ranged stacks depend on it.
Necro Campaign Mission 4
Level Cap: 30
Difficulty Index: 5/6
Last Updated: November 12, 2011
A good starting bonus is the "free first generic hero" bronze-level Dynasty Trait. By now, the starting levels of the generic heroes are very high, making them very expensive to hire. Give this hero and Ludmilla some economic abilities (such as the +1 Wood and Ore per day) and let them ship units to Ana. Another very good bonus at the bronze Dynasty level is "hero +3 movement" (you did pick up Logistics and Pathfinding, right?) You have lots of travelling to do.
Ana starts in the SE corner with a moderately developed Town A. Start with clearing the area close to Town A and flag the resource buildings. Your top priority is to get the Archlich building. The dependable Liches will be your main power output throughout the mission.
Next you can decide to either go north or go west first. There isn't too much difference since everywhere you go, there is a Demon town or fort to conquer. I went north first, and conquered the towns in the alphabetically labeled order (Fort B, Town C.... to Town H), while tackling each underground town in the nearby area.
In my game, I encountered very manageable resistance all the way to Town F. However, by the time I got to Fort Gand beyond, I started seeing enormous inferno army. Maybe that's a good reason to go north first. Or maybe the game will spawn the large armies in the remaining towns no matter where you go first.
You will notice scattered skeleton stacks volunteer to join your army, which contributes to a side quest requiring you to recruit 1000 skeletons. You can collect the skeletons with secondary heroes. You can only pick up a couple of hundreds for free - the others have to come from your accumulated production. This side quest actually serves as a quite accurate "timer" of the mission. In my game, I finished the mission 2 weeks before recruiting enough skeletons. So if you already finish this side quest by having 1000+ skeletons, you should have more than enough power to defeat the final boss.
Let the Blitz begin! Rush to Fort B and bring it down. Convert just the creature building, but not the Fort itself. Save those Wood and Ore to trade for Crystals to get the Weaver building ASAP. Around this area you should be able to pick up your first Moon Shard Fragment. This goes to the second side quest of the mission - collect four fragments, pick up the famous Tear of Asha, and install it in your Capital (your only Level 4 town). The location of the other three fragments are marked by (MF), and the location of the Tear of Asha is marked by Tear. One tricky fragment is located on an island that can be accessed by building a ship from the shipyard southwest of Town E (just west of the future Tear of Asha chest).
It is impossible to acquire the Tear before collecting all four fragments, unlike in Heroes5, where you can dig up the Tear even without having any piece of the map! Note that you have to have all four fragments on the same hero for the Tear chest to spawn. While having the tear installed really boosts your production, you are really better off to conquer as many weak surface Inferno towns and forts as possible at this stage, as even if you get the Tear early, you likely don't have enough resources to install it. Then, when you hit a brick wall later (such as a stack that potentially deals 15000+ damage in one hit), you can take your time to collect the fragments and the Tear.
At this time, you can expect to meet the first demon hero. They are all very aggressive - coming directly at you whenever possible. Curse of the Netherworld is perfect for this kind of small-scale encounter. Throughout this mission I fought more than 10 demon heroes on the field. Strangely, they get quickly "recycled" once they are defeated. So I keep fighting the same two or three heroes 10+ times...
You will also see scattered Shrine of the Seven Dragons throughout the map. However, you can completely ignoring their existence and save the crystals and cash. You can easily reach the level cap without any of them. (So the shrines are not marked on the map above.) Contrary to previous hero games, the EXP curve in Heroes6 does not become very steep at very high levels. However, even after reaching the EXP cap, you can still accumulate EXP for the Dynasty Weapon (both manual and quick combat) and your Dynasty account (manual fighting only). If you feel like it, you can even come back to a previous save just to fight more neutral stacks to farm more EXP, as stacks in mission 4 are all very large and EXP-rich.
Go further north and use the portal (1) to get to the underworld. This portal leads to an isolated area at (1'). It is a good idea to make a secondary hero closely following Ana to pick up resources. As soon as you conquer the Inferno town there (all marked with T), this area will be forever sealed off and any un-collected resources are forever lost. In this area, I found an extremely useful artifact "Boots of the Wayfarer", which increases Ana's movement by 8. Other artifacts you found in this mission are likely to be of very high quality as well.
Next, go north and snatch Town C and convert it to Necropolis as soon as possible. Next, go west and capture Fort D. North of Fort D is a second portal (2) that leads you to the isolated underworld at (2'). Same drill here - demolish the demon town.
Around this time, your home base should be threatened by demon invasion. In my game, I had just enough time to take down Town D (with a very small army - the enemies at the beginning are nothing compared to those at the end) before an enemy hero invaded Town A. By building an advanced Town Portal in Town A (don't build one in Town C!), my Ana instantly returned and sent that poor hero home in no time. Unfortunately, he will be back in no time, too.
It is time to push west now. Fort E is actually very close to Town A. Next go northwest to tackle the third portal (3), leading to another isolated underworld area at (3'). Make it sink into the lava! Keep going west and soon you will see Town F. Convert it to the Dark Side! Up to now the Blitzkrieg should have worked rather perfectly - you made streamline to each target, taking everything on your way.
In my game, when I went down to Fort G, I was greeted by 148 Pit Fiends. While the battle seemed impossible, I was still able to score a perfect victory with Puppet Master and Time Stasis. Whenever the monster stack gets too close, I PMed the huge stack and made it walk all the way to the other end of the battlefield. But that was the last cake battle for me. When I got down to the underworld area at (4)-(4'), I was greeted by an army ten times of my size. Ops. (By the way, my game frequently crashes when a PMed enemy shooter attacks an enemy unit, so be careful.)
When you finally hit the brick wall, it is a good time for Tear of Asha. After a few weeks of roaming and fighting, your army should grow significantly. Eventually you can finish the 4th and 5th underworld town at (5)-(5') with perfect victories.
A tip for these truly epic castle sieges: Do not allow any demon stack gated in front of your Liches. These gated stacks are likely huge thanks to their gigantic mother stack. Once the gating completes, your battle is pretty much over! You have to destroy the gates before the gating completes on the next turn. A reliable way to make sure that happens is to assign your Lamassu and Ghouls, by now your two weakest stacks, to be ready (wait) for gate-breaking every turn, while your other melee stacks take care of the other enemies. The Lamassu takes away 2 hit points from the gate, while the Ghoul can finish it off before the next turn arrives.
The AI will start gating when it decides that it is better off coming out the castle. Therefore, the gating activity will be accompanied by insanely powerful stacks rushing out of that castle gate. Time Stasis is your best friend here. You can try Puppet Master a super stack to hit another (for some huge damage on each other) just before their turn comes up. (If you PM too early, the AI is smart enough to dispel the PM by attacking that stack). If a huge stack reaches your Weavers, you can also use their special ability to tie them up for 2 turns. If you found a Unicorn Horn Bow, definitely use it. It will greatly enhance your ranged power when you most need it. Good luck on these battles - they could be extremely difficult.
Your hard work on the surface is almost complete. The last area is north of the central swamp area. Strangely, I actually found a smaller army defending Town H and the final underworld area of (6)-(6'). But the location of this area both on the surface and underground suggest that they are meant to be the last obstacle. Weird.
After you demolish the 6th and last underground demon town, a one-way portal appears in the middle of the swamp (7). This portal leads you to the final boss fight of the campaign. Uriel has a very long hit-point bar, measuring at 135,000, and he poses a godly, 5-digit Might Power clocked at 13,750! He is also protected by several stacks of "guards" who look like ordinary Haven units. Of course, these celestial guards, who are not really impressive in numbers, are a hundred times tougher than their human counterpart.
While this looks like a very challenging boss fight, it actually feels a lot easier than some of the castle assaults before. First, you can take your time to visit all the one-time battle bonus buildings on the surface without having a gate-camping hero to negate them all. Second, your towns should be producing an absurd number of units every week. In my game, Uriel quietly went down in just a few turns in an anti-climax "perfect loss". How's that challenge for the campaign finale?!
Indeed, if you find any battle in this mission too difficult, simply fight some neutral stacks to pass time and let your town production gives you the edge later. If you win a battle with heavy casualties, it is also a good idea to not fight it now, but to come back a few weeks later. Chances are there is another very tough battle after this, so you don't want to waste your precious cash on reviving a large number of fallen units. You need the cash to hire the next week's new recruits. By avoiding all heavy-loss fights, you might be able to use fingers on just one hand to count how many units you actually had to bring back from the Altar of Eternal Servitude throughout this mission. That's how powerful a necromancer is, or rather, how simple this game could be even on Hard difficulty. The only thing that gets hurt is your mission score (for taking longer to finish). However, you are still very likely to receive the highest rank (hero) if you play on Hard. (p.s. Currently (v1.1.1), you don't get any achievement from completing missions with a "hero" ranking.)
Anyway, congratulations for beating the Necropolis campaign! I hope you had lots of fun in those epic siege battles like I did.