Bowser Jr.

When Bowser Jr. deals combat damage to a
player, create a 2/2 green Koopa token with,
"When this creature is dealt damage, exile it and
create green Koopa Shell token."
Bowser Jr. has +1/+1 for each other Koopaling
you control.
{r}{g}{t}: Search your library for a Koopaling card, reveal it, and put it into your hand. Suffle
your library.