Very old but kickass band, I think they are fairly well-known but not known enough. I just can't get enough of this band:
https://www.youtube.com/watch?v=HmwIWGCTLYA
https://www.youtube.com/watch?v=s2LhHcJa5uQ
https://www.youtube.com/watch?v=VlGVxbuTMQI
Thomas Rettke sounds a little bit Tony Moore-ish, but other than that, one of the best singers of Power Metal for sure.