Prism, Advent of Thrones [DTD002] (Dusk Till Dawn)

Whenever a card with Herald in its name is put into Prism's soul during an action phase, you may search your deck for a figment, put it into the arena, then shuffle. Once per Turn Instant -- (2 - Resource), banish a card from Prism's soul: Awaken target figment you control. (Flip it.)