Essence of Orthodoxy is a rare Creature — Phyrexian card from March of the Machine (MOM), collector number 376. Current market price: $1.53, TCGplayer market prices via Scryfall.
Flying Whenever this creature or another Phyrexian you control enters, incubate 2. (Create an Incubator token with two +1/+1 counters on it and "{2}: Transform this token." It transforms into a 0/0 Phyrexian artifact creature.)