@tsukuyama, drag the piece onto where you wanna cast the magic as if you were moving it there. If it still doesn't work, make sure the magic's target is in range.
@KarthikG2 you have to wait until you get the hero called amenhotep. He is the 19th hero and the one after ma zhu. When you get him level him to 150 then buy the upgrade called ASCENION which costs 38400q. I recommend you ascend when you are able to get 10 hero souls, then next ascenion 15, then 20 and so on. Further guides are available on the forums. :)
The sad part is that I didnt even notice that pressing down over the words activated them, i just pressed down everywhere hoping to find some thing -_-
 "I Am An Insane Rogue AI")
 "Chess Evolved Online")
 "Mutilate-a-Doll 2")
 "Superfighters")
 "Raze 3")
 "Clicker Heroes")
 "Words Warriors")
 "Contract Wars")
 "Battalion Commander")
 "Family Rush")
 "Strike Force Heroes 2")
 "Ruthless Pandas")
 "Epic Time Pirates")
 "Falling Sands")