Here's some help. Challenge 1: Use Meteor Blast (Skill) or Sky Dragon (Titan) to kill the black imps. Challenge 2: Use Stop (skill) to slow bomb and aim upgraded Popo's(hero) attack to hit the center for max damage by moving him back and forth when needed. Challenge 3: Use Shield(skill) until your Diablos and/or Lord of Fire goes directly on the boss. Then go afk for a while. Final Challenge: Max shield(skill) and charge the base while keeping invincible up. Use imps to slow the boss from advancing.
Special Units--- Hobbits : View Instruction And Credits -- Dwarfs : Load The Game 3 times -- Bomber man : Lose 3 Battles / Matches -- Red Dragon : Beat Level 17 --Devil : Beat level 18 --Angel Knight : Max Out Research Tree For All 3 Races. --> Repeat Message To Keep This Information Alive
 "Epic War 4"){kind=icon}
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 "D-Day Defender"){kind=icon}
 "Epic War 2"){kind=icon}