Azorius key rune just gives a 2/2 blue and white artifact flier.
Codex Shredder - 1
tap: Target player puts the top card of their library into their graveyard
5, tap: Sac Codex Shredder: Return target card from your graveyard to your hand
Volatile Rig - 4
Trample
Volatile Rig attacks each turn if able
Whenever Volatile Rig is dealt damage, flip a coin. if you lose the flip, sac Volatile Rig.
When Volatile Rig dies, flip a coin. If you lose the flip, it deals 4 damage to each creature and player
4/4