It was an idea from me, JA-punkster.
I created a Dragon Koopa calls Somhairle, a far celtic uncle of Bowser. He is the ruler of the Black Island on Lavalava Island aka Dinosaur Land. Black Island is the Isengard of the Mushroom World. A location of Industry and Progress. Paragon was the Isengard of Saruman in Middle Earth.
And the Black Yoshis are the minions of Somhairle. But unlike Bowser and his henchmen, Somhairle and his Yoshis are great allies of the Blue Koopa Turtles and the Super Mario Brothers.