Enable the "all buildings" code to access special structures. All special structures give 50% creature growth, +5000 gold income, and has a special attribute:
STRUCTURE - LOCATION/ATTRIBUTE Aurora Borealias (Conflux) - Located above castle; all spells. Spirit Totem (Rampart) - Located beside castle; Luck +2 . Deity of Fire (Inferno) - Located beside town hall; all weeks declared Week Of The Imp. Soul Prison (Necropolis) - Located in front of the blacksmith; increases Necromancy skill by 20%. Carnivorous Plant (Fortress) - Located on a plank in the water; increases attack and defense of a garrison hero in a siege. Skyship (Tower) - Located behind Temple Of The Clouds; gives full world map, increases defending hero Knowledge +15. Guardian Of The Earth (Dungeon) - Located under the Dragon Caves; increases defending hero Power +12.
The AI will try reducing stacks of your cheap units (for example, pikemen, goblins, centaurs, etc.). Put 60 to 80 of them in with an army to draw attacks, then go in and attack the enemy's powerful units while they are distracted.