Dark Bowser,Nightmare Star

Trample, Menace
When "Dark Bowser,Nightmare Star" enter in the battlefield , transform "Koopa" token to "Dark Koopa".
Whenever Dark Bowser,Nightmare Star attack,
create one 2/2 "Dark Koopa" creature tokens.
{b} {b}: Sacrifice all "Dark Koopa" creatures you control.
Bowser, King of the Koopas gets +2/+2 for each "Dark Koopa" creature sacrificed this way until end of turn.
{r}{u}{u} : Dark Bowser gains hexproof until end of turn.