Draztal explains a bit about how the progression of Icecrown will work and I think those are the details that interest players the most.
It was to be hoped that some method would be introduced to increase the duration of the dungeon, so that the gap between Icecrown and Cataclysm would not be too great. Personally, I find it great that it is necessary to defeat a boss in normal mode in order to defeat him in heroic mode. However, I have my serious doubts that any of the initial encounters can be defeated in Heroic mode with this scheme during the first few weeks.
Another point in favor that I see is the explanation in the history of World of Warcraft (lore) and that it does not have a greater explanation as could happen in the Trial of the Crusader. It is clearly observed how at the beginning Icecrown will be quite difficult and, with the passage of time, the difficulty will be reduced thanks to the supports received by our Faction leaders.
However (There is always one) the limitations of attempts to Professor Putricide, Queen of Blood, Sindragosa and the Lich King seem a bit to me ... Here I think that the meaning of "week of attempts to boss X extending the save to learn it" is lost. impossible, if you extend the save you will still not have Putricidio. Arthas will be practically inaccessible at first, you will have (once all are unlocked) 15 attempts to finish them all and, as a general rule, there will be some death in one of the bosses leaving you for Arthas a few attempts.
So I have to say that my feeling is bittersweet about the changes.
What changes? Oops! I almost forgot…! After the jump you have the explanation of Draztal:
The Icecrown Citadel trials have progressed very well over the past few weeks, and this has been a great help to the battle design team. We want to thank everyone who has accessed the PTR and tried the fights there.
Now that we are getting closer to the release of 3.3.0, we want to talk about our plans for access progression within Icecrown Citadel. Icecrown Citadel will be divided into four different sections: the Assault on the Citadel, The Plague Workshops, The Crimson Room, and the Frostwing Halls. We plan to release these four sections of Icecrown Citadel over time and not immediately when patch 3.3.0 is released. At this time, we cannot give you precise dates for the release of these as they are determined by when patch 3.3.0 is released. Once we know those dates with more certainty, we will inform you so that you can plan properly.
The first section to open will include the fights with Lord Marrow, Lady Deathwhisper, the Naval Battle of Icecrown and Deathbringer Saurfang. Progress beyond that point will be restricted for several weeks. Later, the Plague Workshops with Carapútrea, Panzachancro and Professor Putricidio will open. After another period of time, the Crimson Room will open and you will be able to fight the Blood Princes and Blood Queen Lana'thel. Finally, the Frostwing Vaults will be unlocked, allowing access to Valithria Dreamwalker, Sindragosa, and the Lich King. We believe that a staggered release of content will allow players to experience Icecrown Citadel at a more sustainable, restrained, and ultimately more enjoyable pace.
There are other elements that limit access along the way. Players will not be able to attempt the 10-player Heroic versions until they defeat the Lich King in 10-player mode. Similarly, players must defeat the Lich King in 25-player mode before they can face a Heroic 25 battle. So players must master each fight on normal difficulty in Icecrown before attempting Heroic difficulty.
It cannot be tested against the Lich King until Professor Putricide, Blood Queen Lana'thel, and Sindragosa have been defeated. Additionally, the Lich King Heroic Difficulty cannot be tested in a given week unless all three fights mentioned above have been defeated in Heroic mode that week.
The Ashen Verdict provides reinforcements and material for players to storm Icecrown Citadel, but this support is not infinite. Raids will have a limited number of total attempts each week to defeat the four toughest fights in Icecrown Citadel: Professor Putricide, Blood Queen Lana'thel, Sindragosa, and the Lich King. As these fights are unlocked, the number of attempts available per week increases: the initial number of attempts provided to defeat Professor Putricide is only 5. When Blood Queen Lana'thel is unlocked, the number of total attempts will increase to 10. When Sindragosa and the Lich King are unlocked, attempts will increase to a total of 15 to defeat all four bosses. After a raid has exhausted their attempts for that week, the Ashen Verdict must withdraw their support and the four most difficult bosses disappear and become unavailable for the rest of the week. The limited attempt system on a feature in both Normal and Heroic modes.
There will be no explicit rewards for defeating the Lich King with a certain amount of tries as there were in the Trial of the Great Crusader. There will also be no achievement for completing Icecrown Citadel without being defeated by a boss or letting a raid member die (such as A Tribute to Madness).
In the weeks and months after all twelve battles are unlocked, more attempts will be available against the last four bosses. This represents the growth of the Ashen Verdict, becoming more powerful and gaining greater control of Icecrown Citadel. To further aid the gangs, Varian Wrynn and Garrosh Hellscream will begin to provide aid to the armies by inspiring them to attack Icecrown Citadel. This is represented as a spell that covers the entire area applied to all players that will increase their hit points, damage dealt, and healing done. This effect will also increase in effectiveness over time. Players can override the spell's effect if they wish.