My EGO rating is 1219 and I have fought against Nim in 114 times, and I lose every time, no chance. But then when his red health-line is the middle, the whole thing freezes and nothing happens.
Is this supposed to be really hard ?
How to win the Nim in Terra-spire control room?

I've played this game almost half a year, problem has been the same.
Do I make something wrong?