P03, the Scrybe of Technology

Ward {3} - Sactifice a Legendary Artifact or Legendary Creature
When P03 enters the battlefield and whenever
you cast an Artifact spell Venture into the dungeon.
Artifact spells you cast have casualty 2 (activate only twice each turn).
When P03 attacks, defending player reveal 3 cards. Chose one and create a copy of it under your control. Then put the cards revealed this way on the bottom of the library in any order.