Dragetinace

Use the giant arrow and rocket backpack to snipe air defences....and by allowing the duke to go to the other corner, he gets isolated and his ability activates...also use ice block spells if the duke is low on health

From the side of the queen, unleash the ground terror...the barbarian king+ 2 ice golems+ 2 super yeti easily finish 30% to 40%....remember to use rage spells here

Then unleash the grand warden with lava hound, e drag, drag, drag rider and super balloon....use one or two super balloon before this air spam to take on air traps

Finally, behind them place your siege machine...the balloon and minions can easily clean up...

Use eternal tome in the core of the base...and freeze monoliths or single target infernos....and use invisibility along the way...like when they are travelling to the core...