If its the game im thinking of then Lieutenant Surge
gem leader blue
Giovanni, he has rock type Pokemon
Red is in mt.silver and blue is the eight kanto gym leader
You have to make a new game
the 16th gym leader is:Trainer Blue
It could be Blue or Clair.
Blue, the last gym leader in kanto region
Blue is the Viridian City Gym Leader (Badge #16)
i am not sure about if they are the leader but they can be a partner
Cinnabar Island.
seafoam islands
you need hm 1 cut