The Kane Identity

I'm sure this has been discussed, but does anyone remember when Kane first came out and he was huge? He was taller than the undertaker and bigger too. He towered over test and could pick up the Big Show. Then does anyone remember when Kane came back from like a long injury and he had that like half mask on and test was now as tall as him and he was smaller than prince albert? Or how about more recently when he faced undertaker at wreslemania.... i believe he looked smaller than undertaker. I cannot believe that he has been the same guy behind that mask. Please someone give me some answers!!!!