Therizinosaurus Broodmaster

When this creature enters the battlefield, create two 2/1 red and green Theropod creature tokens.
As long as you control another Theropod, this creature has defender, first strike, and gets -3/+3.
As long as you control no other Theropods, this creature has double strike and menace.
{r/g},{t}: Create a 2/1 red and green Theropod creature token.