Jack, The Giant-Killer

Whenever a creature with power 4 or greater leaves the battlefield, add {g} or{r}, and create a 3/3 green and red Elemental Beanstalk creature token.
{t}destroy target creature with power 4 of greater
When Jack enters the battlefield, create a green and red Elemental Beanstalk creature token with power and toughness x, where x is the number of times you've cast this card from the command zone this game.
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