I personally don’t care for another version of the forge (lone player activity) preferring something the alliance players can share. But I like this basic idea.
Instead I would create an advanced building called a Mercenary Guild. At Level 1 you would unlock Quest: McGuffin. The McGuffin would be a 3* Ascension item. The McGuffin Quest would run just like the rare quests (example Frostmarch), but be visible only to the alliance. The entire alliance could participate in the McGuffin Quest.
To start the McGuffin Quest would require X number of Alliance players to donate a single 3* Ascension item, but it could be any surplus 3* Ascension item. Only co-leaders, or leaders, can activate an alliance rare quest after enough Ascension items are donated. As each player donates an Ascension items, any eligible rare quest would become available for the co-leaders, and leader, to activate for the whole alliance with other alliance rare quests showing the needed donations.
Example
Quest: Compass (3* Ascension item) might require 8 alliance players donate one 3* Ascension item. The seven players donate 5x Chainmail Shirt, 1x Hidden Blade, 1x Trap tools. This shows Quest: Compass 7/8 to the co-leaders and leader. Another player donates a Chainmail Shirt. This shows Quest: Compass 8/8 to the co-leaders, and leader, and lets them activate it for the entire alliance.
Alliance rare quests for 4* items would require the donation of Y number of 4* items. Total number of items might vary by quest.
Built in limitations include, X alliance players would need a Mercenary Guild to activate each rare quest. Since each player can only donate one item, X alliance players would need surplus Ascension materials to activate each rare quest. Only the co-leaders, or leader, can choose and start an alliance rare quests. Completing the rare quest would require Y world energy and Z power team.
Advantages to alliance rare quests include, getting the Ascension item you want while trading a surplus Ascension item. Getting normal map loot in addition. Low level players can still get loot from the early stages of the quest, even if they don’t finish the whole quest and get the Ascension item.
Business note: Players would spend time, or gems, to improve their hero teams to complete alliance rare quests. Players would spend time, or gems, to collect Ascension materials to donate to their Mercenary Guild to fuel alliance rare quests. Cash players would spend gems on world energy. Lower level stages would allow new players to participate in the quests.
Alliance rare quest ingredients
The Mercenary Guild could also have Quest: Unobtainium. Unobtainium would be a 3* ingredient. To active the Unobtainium Quest would require X number of Alliance players to donate a single 3* ingredient, but it could be any surplus 3* ingredient. The Unobtainium Quest would run just like the alliance rare quests for Ascension materials.
Alliance rare quests for 4* ingredients would require the donation of Y number of 4* ingredients. Total number of donations might vary by quest.
Bonus Stage option
Each Quest: McGuffin and Quest: Unobtainium would have a final bonus stage for very high level teams. it would award double the quest prizes and award both an Ascension item and a ingredient.
Example:
Quest: Fine Steel would award Fine Steel for completing the second to last stage. Completing the last stage would award Fine Gloves (bonus Ascension material) and twice the Fine Steel of the previous stage (for a total of three times the Fine Steel). This bonus stage would be very challenging.
Data
Empire ranks?
leader
co-leader
elder
***member (no promotion required)