How I beat 19 + levels:
Expand your village and make a decent army that can hold the enemy off for a while, but do not use ANY other abilities than Terraform. You wanna save mana for the Water Storm. After you build up your army and the enemy starts closing up on you its time to peace out. Go far away from the enemy as possible (using way point) and try to destroy that way behind you. By that time you should be close to 500 mana for your finisher . After you start the Water Storm (it destroys all blocks) make sure you build some blocks under your guys before they drown and you win the game. Hope this helped :)
HyoriLee@
Try going Magnus Steelblade and turtle yourself in base. Build some warriors/knights and when the enemy attacks use Iron Skin(throw in some Titanic Growth if its looking bad). You should be able to survive like that. After you upgrade your resources you should be ready to strike. Defending your base should be no problem by now so just keep using Titanic Growth on knights. After you gather like 2-5 knight Titans you can attack and win the game. Hope this helped :)
btw. This strat basically works against any hero (at least its how i played it)
You need to spend some points into the Demonic tree for Silence, otherwise the fights with guys that have regen get really frustrating.
You can switch the active spells for other ones(in the skill tree, click the one from the slot and one from the tree), but I dont think you can clear them out.
Siege fights: Let your catapult/dragon destroy the castle or destroy enemy units with archers and then use your ram on the castle.
Boss fights: Always keep the boss silenced all the time. Then you win.
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