I beat cot 1 with only 995 mana. 2nd try really difficult and takes awhile. Goblin, dwarves, Taurus, elves, bomber, comet, healing , Phoenix. Do this if you want a challenge
Finally beat cot 5 with only mermaids, goblins, dwarves, and comets. It was quite difficult and took forever. Took awhile to find a winning strategy. When i had my full unit i had my knight all the way up there and my mermaids. I waited till the mermaids got close enough to push back the invisible goblin consistently. My knight took care of the pesky goblins and bombers. Then i rushed my whole army. It worked out pretty well the invisible goblin kept on getting pushed back by my mermaids that he couldnt even kill my units. I also got lucky that his knight didnt respond otherwise my unit would be wiped out.
To be level 17 with the humans. You will need massive amounts of wizards, spamming hobbits and angel soldiers. You can throw in the arch angel but i consider it a waste of mana. Use the arch angel or angel soldiers to get rid of the big waves and pull back the enemy. When the enemy's castle is destroyed you need to have on the field many wizards and at least an angel soldier. The end doesn't hurt the angel solider that much only damages it 200 each time. The angel soldier will pull back the enemy's army as well as damage the end. Wizards help alot to reduce the End's life points. The arrows will be the most effective weapon against The end. Spamming hobbits will slow down the End movements. I hope this helps you
To defeat the Lord of Hell with the human race all you need is red dragons and angel soldiers. The hard part is getting rid of the big waves which consists of millions of orc riders, paladins, elf soldiers, dragons, devils. Once you get rid of the big waves the rest is easy. The Lord of Hell will not ground pound angel soldiers or red dragons. You can have as many units on the screen and The Lord of Hell will not trigger his gp. It is only triggered when a unit is too close to him. You could use arch angel titan to push the enemy back but it cannot be there when the Lord of Hell comes
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