Rohaggh, Chosen of Prossh

When you cast Rohaggh, Chosen of Prossh, all
Kobolds gain +x/+x until end of turn.
When Rohaggh, Chosen of Prosh leaves the
battlefield, you may search your library for a card
named Prossh, Skyraider of Kher, reveal it and
put it into your hand. Shuffle your library afterwards.
Whenever you cast a creature spell with a
converted mana cost of 0, draw a card.