In total there are 3 different realm (server) types in DHD!
Heirs of the Dragon (General ) Realms
This is the most common version of the game.
You build up a city, feed your dragons, recruit generals and train troops, gradually progressing each feature through levels. You can choose to defend your city walls in one of three ways, either with your whole army, part of your army or not at all. Wall colour will change accordingly .
Just as it sounds - one hardcore version of DoA:Heirs . Your troops are always protecting your city. No possibility to set up even a so called custom Wall. The good news is that only 50% of your troops die at each attack, and as well as the Healing Pools, there is an Altar where troops can be brought back from the dead - but it not called hardcore without reason. Alliance support is fundamental to your success!
Dragon Age Realms
Gameplay is similar to Hardcore - as you are always defending your city. But here you have slightly different troops, generals, and battle mechanics, and different battle reports - and all troops involved will die. You get statistics over your progress. This is a fun and challenging version of the Game!
Each version has in common that you get rewards for daily login and daily quests. You set up an army to fight in the Arena and get your dragons to challenge other dragons in battle in a dragon battleground scenario - Plus a lot more!
Tip: When choosing your Realm, pay attention to local server time and stress, as they sometimes affect Tournament times and rewards ;)