Lin Sivvi, Protector of Rath

First Strike
At the beginning of your end step, you may
search your library for a Rebel card and put
it into your graveyard.
At the beginning of your upkeep, if you have
seven or more cards in your graveyard, exile
Lin Sivvi, Protector of Rath, then return
her to the battlefield transformed under
her owner's control.
{w},{t}: Create a 2/2 white Rebel creature
token with First Strike.