This gets better the more players you have in your games, and so is naturally at its worst in Cube, where cards at this mana cost get cheated into play and do a lot more to win the game than come with two [card]Phyrexian Arena[/card]s
Since blue has lots of cheap bounce spells like Chain of Vapor or Cyclonic Rift you can easily bounce a threat to your opponents hand and make them discard it with Amnesia
Then the recently printed Offering costs two too, also sacrifices both, and this time leaves you a Map token to either draw the top land of your library for a three for one, or give a dork a +1/+1 counter
This sorcery allows you to exile the top two cards of your library and play them until the end of your next turn
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