Jeskai Infiltrator can't be blocked as long as you control no other creatures.
When Jeskai Infiltrator deals combat damage to a player, exile it and the top card of your library in a face-down pile, shuffle that pile, then manifest those cards (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.).
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