Johnny, Combo Player

{4}: Search your library for a card, put that card into your hand, then shuffle.

Grinding Station

{T}, Sacrifice an artifact: Target player mills three cards.
Whenever an artifact enters, you may untap Grinding Station.

Whenever a nontoken creature enters, if Genesis Chamber is untapped, that creature's controller creates a 1/1 colorless Myr artifact creature token.

You may cast spells as though they had flash.

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.