My expansion pits the horde alliance as well as wow classic tbc gold the Horde. You fight for the control of neutral zones in order to control Azeroth. You can access more flight routes and quests as you are in control of a zone. There are quests available while attacking a particular zone to help your side regain control of the area. Instead of having to kill 10 raptors while leveling to maximum level, join in the fight. Once you have taken the control of a region, you get new quests to try and maintain control, the zone will change depending upon which faction controls it. Horde is controlling it? Alliance is home to a couple of outposts and must slowly advance. The world is in a battle with NPCs fighting with each other as well as players. Ressource transportation is secured for various zones and then protecting them from the hostile faction.
LocalDefense channel is used to announce attacks by enemies at outposts or towns, and to facilitate communication between players. Your group can get the resources gained from winning battlegrounds for the fight. New battlegrounds are created to match with each neutral zone (alterac valley = winterspring warsong = barrens, and so on) You can also queue up for the battlegrounds or zones that require assistance. The war effort you put into it will allow you to upgrade your equipment at any level you can gain rank in your faction, and get access to mounts/tabards as with other gear. Make use of your skills to make weapons and equipment needed during the conflict.
There's surely more that can be added to this fundamental idea, as well as several other aspects in vanilla which made for an excellent base, but I've not seen any follow-up.
The design is not perfect, and there are flaws I am aware of. For example, the differences in max level characters and cheap wow tbc gold the imbalance in factions. But just thinking of this is a reminder of how much potential WoW was able to fulfill, even though it was already an excellent game.
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