Rathalos, Aerial Emperor

Partner with Rathian, Terrestrial Tyrant (When this creature enters the battlefield, target player may put Rathian, Terrestrial Tyrant into their hand from their library, then shuffle.)
Flying, Agility {3}
{r}: Rathalos, Aerial Emperor gets +1/0 until the end of turn.
{r}: Rathalos, Aerial Emperor deals 1 damage to target creature an opponent controls.
Whenever a creature with flying enters the battlefield under
an opponent's control, Rathalos, Aerial Emperor deals damage equal to its power t