My main strategy of how I won DM was to prepare for incoming attackers instead of getting an army with no Skill.
First you need to prepare about 3 units (recommended Meric, Albowtross, You Choose). While that trains, prepare the Miner Walls and Castle Archidons in case of an attack. Once that's complete, begin developing skills for each of your units. It would be wise to have a Tower Spawn at your disposal.
Around this Time, the enemy would be launching their attack. If correct, your 3 troops and defenses will hold Them off for a while. If the attack stands for at least 10 seconds spawn Swordwrath to deal with them till they retreat.Now is the time to develop troops and capture the central tower. By that time. Victory is up to you.
Stick Empires Wiki LancelotVII or User: Honeflasg
The strategy I use is fist buying albtross and tower spawn . Then I take over the central tower while the tower spawn is researching. Then gather an amry of Albowtross and Meric. Then if your emeny is attacking the tower spawn is ready.If you defeated your emeny amry,when you have enough buy tower spawn 2. If you don't, retreat. Then gather your amry. After you did attack. You should win the fight. Then take the center tower again. When the giant is ready attack. You should also win too.