Mike Scott and Randy Johnson are as unhittable as I've seen anyone. They just made people look foolish. I don't know if remember correctly but I think Mike actually got someone to swing at a pitch that ended hitting home plate because it dropped so fast.
You know, I considered including relievers. Lidge had a dominant 2004. 1.90 ERA, 29 saves, 157! strikeouts, along with a .919 WHIP. But I still think Wagner's 99 season was better - 1.57 ERA, 39 saves, 124K, and a .777 WHIP. It really depends on how much you value Lidge's additional innings over Wagner's better per-inning statistics. Both are among the top-10 relief pitching seasons ever by WAR or WPA.
Don Wilson's 2.45 and 18 complete games. Nolan's 8-16 year when he led the league in ERA. JR's..last year before the stroke. ( Year before was good too) Randy Johnson's stretch..
I'll see your Don Wilson and raise you a Larry Dierker - 2.33 ERA, 20 wins, 20 complete games, 232 strike outs, 22 years old.