The Vortex Campaign unleashes a number of stressful surprises on a first-time player, from enemy doomstacks spawning in your own territory to short windows of time to act. I have created this guide to give the wise the knowledge they need to understand and prepare for these surprises and thereby avoid the frustration of having to reload a previous save from many turns prior, or perish the thought, having to restart a whole campaign.
Guide to Eye of the Vortex Campaign
Reason for Guide
I have seen a large number of Reddit and other forum posters say they hate the Vortex campaign; or they simply never play it because there is Mortal Empires. Others post about how they were not ready for the final victory condition event and lost or had to load a far previous save file to prepare better. That happened in my first Vortex campaign with Kroq-Gar, I realized I was not ready (I didn't have Kroq-Gar ready with a doomstack) and had to reload a save to better prepare. There is also the unpleasant stress of seeing 6 enemy army doomstacks spawn in your own territory that nothing prepares you for. At least with the Chaos Invasion in Warhammer 1 and Mortal Empires, Chaos spawns in a specific area and then moves toward your territory, like the Huns in Attila. Obviously if you do not know how the campaign works it would be prudent to play a Normal to Very Hard (NOT Legendary) difficulty campaign and save every turn so you can learn the campaign and reload previous saves if you realize you screwed up. But why must thousands of players suffer such thousands of hours of wasted time due to reloading even just a 5 turn previous save file, when those with experience have the knowledge to prevent that. I regret not making this guide sooner, but I shall rectify that now. Enjoy this guide on how to prepare for the Vortex rituals and the Final Battle.
Note that some Races and Factions do not participate in the Race for the Vortex even when playing on the Vortex map. Tomb Kings, Vampire Coast, Snikch, Malus Darkblade, Nakai the Wanderer, The Huntsmarshal Markus Wulfhart and Repanse de Lyonese have their own victory objectives on the Vortex map. The other DLC factions like Alarielle, Alith Anar, Tehenhuan, Gor-Rok, Tik'taq'to, Hellebron, Lokhir Fellhart, Tretch Craventail and Ikit Claw are normal Great Vortex Race factions.
Beginning with the End
To win the Vortex campaign, you must win the "Final Battle". If you complete the Final Ritual, you will have Five (5) turns to start the Final Battle, where you will be the Defender.
Quick Very Important Note! You need to be ready with your Faction Leader (the Legendary Lord you started the campaign with) and a Top Tier army ready to go or at least able to be recruited immediately (you do not want your leader in a wounded state), because if you are not ready and do not fight the battle within the limit, then you have to repeat the Final Ritual, which takes 20 turns and spawns multiple doomstacks TWICE during those 20 turns!!!
The Final Battle consists of each of the other 3 ritual race factions' primary Legendary Lords (Tyrion, Malekith, Mazdamundi, I think Queek for the Skaven but not certain) attacking you in waves to try and stop you from winning (thankfully they don't all attack you at once, the next army enters the battle as soon as you defeat the previous enemy). Then I think one final enemy force (I think Skaven) makes a final assault to stop you. If you win, you win the game, if you lose, you lose the game.
Important - The AI can finish the final ritual before you. If they do, this will also prompt the Final Battle with 5 turns to fight it, where you will be the attacker and must attack and win. If you win, then the faction who started the ritual is out of the competition; but you have not won the game yet, you still must continue on with your rituals so that you can do the Final Battle as the Defender.
Even if you kill Malekith, Mazdamundi and Tyrion's factions before you start the Final Battle, they will still be present leading their armies in the battle. If you kill the primary ritual race faction of a given race (such as defeating Tyrion/Lothern of the High Elves) but other factions of that race survive (such as Teclis of the High Elves), the next faction in line of that race will take over trying to complete the ritual. Only once you have completely destroyed a race do you not have to worry about that race finishing the ritual before you.
Important - The most important thing, whether you or the AI complete the Final Ritual and can start the Final Battle, is that your Faction Leader be "alive" (not wounded since s/he is Immortal) and ready to go with a doomstack of the best units you have. This is not a time to be playing around with Skaven Clanrats, Skinks, High Elf Spearmen or Dark Elf Bleakswords. I recommend an army of 19 Star Dragons for High Elves, 19 Black Dragons for Dark Elves, 19 Carnosaurs/Stegadon/Ancient Stegadon for Lizardmen; and for Skaven - Doomwheels and/or Hellpit Abominations, either 19 of them or 9-11 of either/both supported by 9-10 Plagueclaw Catapults and/or Warp Lightning Cannons (because Skaven artillery is so awesome). Lord + 10 Doomwheels + 4 Warp Lightning Cannons + 5 Plagueclaw Catapults is a good guideline.
Key Point - During the final battle you get a couple of very powerful spells that have unlimited uses. One is a damage spell that is a powerful explosion you can drop anywhere, and the other is a healing explosion that heals your units. So you can be nuking the enemy as they enter the map, while if your Star Dragons take some damage, you can heal them back up to full health with the heal bomb. So really, as long as you did not bring crap tier 1 units to this fight, the battle should be easy to win.
Every time you start a ritual, a number of AI armies spawn in or very near your territory that will beeline for a ritual city to try and Raze it in order to stop your ritual. If a ritual city is destroyed and you do not re-colonize it before the ritual completes, the ritual fails, and you have to start all over (and spawn another 4-6+ doomstacks that will try to do the same again); the same rule applies to the AI factions. If a ritual city is destroyed at the start of the ritual and you destroy the AI doomstacks and re-colonize the city, it is annoying but the ritual should still complete and you can continue on. Really sucks though when the AI sneaks up on a ritual city and destroys it just before the timer is up. Even more annoying, they may not just beeline to a ritual city; they may raze as many of your settlements as they can along the way, so while you can just stick a "perfect-for-siege-defense" army in each of the 3 cities and wait for the AI to come destroy themselves against your walls, they could wreck your economy along the way. Some forum posters have noted that this actually seems to be the AI strategy in recent game patches, they do not go for the major ritual cities but instead attack all the weak targets they can. So it is a good idea to prepare for them with armies around the area they will spawn in to annihilate them quickly before they can rampage.
Important - The Final Ritual spawns 6+ AI doomstacks at the start of the 20 turn ritual, and then another 6+ doomstacks after 10 turns remain in the ritual. Be prepared for that Second Wave.
The AI spawns may all spawn inland, they may spawn some inland and some in the sea, or they may all spawn in the sea. For example, my Ikit Claw campaign, they tended to spawn near Itza, near Tlaxtlan, and during earlier rituals they spawned a couple in the ocean east of The Awakening.
Key Note - In my Ikit Claw campaign I got lucky because they consistently spawned in the center of Lustria between Itza and Tlaxtlan, even once I owned Naggarond and most of Naggaroth. I made sure not to mess with this spawning by making sure that my armies stayed well outside the central area they were spawning in. I think that if you see where the AI spawns the armies and have armies right in that area, the game sees your prepared ambush and has the AI armies spawn somewhere else, completely messing up your plans. I noticed this in my Tyrion campaign, where if I had too many armies in one spot I thought the AI would spawn at, they spawned elsewhere, but if I moved my armies back from that spawn location (but still close enough to move to defend my cities in time), the AI would then spawn where I thought they would.
Another important point is, if one of your ritual cities is on another continent, the AI could spawn the doomstacks all near a city you are not expecting, or even split them up between them. This is one of the reasons that if you want to just win the Vortex Campaign via doing the rituals and have as easy and stress-free a campaign as possible, you may not want to be all over the map, you may want to just capture you continent and camp there. So as Tyrion only capture Ulthuan and then do rituals while having your armies around the island to respond to the AI spawns; as Clan Skryre or Pestilens, secure Lustria (South America) and then camp in a wide circle around Itza; etc.
In addition to all this fun, just like you can send Intervention armies against the AI ritual cities, they can send Intervention armies against yours. And they can pick the worst timing for you as well. They never sent Intervention armies in my Ikit Claw campaign (I think I damaged their economies so much that they couldn't afford to), but they did a bunch of times in my Kroq-Gar campaign; your luck may vary.
The Ritual Process and Intervention Armies
Each faction racing for the Vortex must collect enough ritual currency to start a ritual. You can collect ritual currency a number of ways, but for a steady supply, you want to capture settlements with the ritual currency resource (there should be one close to the starting area of each faction) and be sure to build the building that provides the ritual currency every turn. You can have all the ritual currency you need saved up before you even start the rituals, I'm certain I had all the currency I needed for the final ritual before I even started the 4th ritual in my Ikit Claw campaign, maybe even by the 3rd ritual (maybe even earlier, it was 184 turn campaign and I waited a long time to start the rituals).
Each ritual has an increasing cost of ritual currency, and has different effects. Ritual currency is generated through settlements, treasure hunts and other dilemmas, winning battles and also through ritual resource sites. The ritual currency is different for each race, it tells you what that resource is called for your race on the ritual bar.
Rituals progress in a linear fashion, one after the other. During a ritual, 3 of your settlements (or the AI's) funnel magic across the map to the Great Vortex. Successfuly destroying any of these settlements will stop that faction's ritual. Regular rituals take 10 turns to finish, the final ritual takes 20 turns, so the settlements must be protected from Warriors of Chaos and Norscan Tribes factions (and Skaven) who will spawn nearby, and from enemy Intervention armies.
Each completed ritual will cause a cutscene to play that furthers the story.
Intervention armies can be summoned while another faction is in the middle of performing a ritual. These armies are AI controlled and generally attack the enemy settlements involved in their ritual. Interventions come in 3 levels, which cost different amounts, 2K, 5K, 10K. The 10K army is the most powerful and therefore has the best chance of successfully destroying an enemy's ritual settlement, and since you can only summon 1 intervention per ritual per faction (so you can hit each of the other 3 ritual race factions with a 10K intervention when they start ritual #1, again when they start ritual #2, etc), it makes the most sense to use the 10K option if you can. Sometimes it will be like throwing $10k away because of how ineffective the Intervention army is, sometimes it gets the job done nicely (in my Ikit Claw campaign, a $10k Intervention army destroyed the city on the island in the middle south of the map, causing the an elf faction to fail their ritual; this is also an example of ritual cities being so far apart that a faction cannot support that city if it is targeted).