Additionally, when a Zombie Monster is Special Summoned from either Graveyard, you draw one card
The harmonize cost is steep, but your own scaling creatures make it easier to cast from your graveyard
(There was a time when there was no maximum limit, which swiftly changed after someone entered a German tournament with a 2000+ card deck.) A tournament deck will always be 40 cards because the fewer cards you have, the more likely you are to draw the ones you want
Regular Astartes wouldn't dare be menacing in their vigilance
You can banish this card from your hand or field
In every game, you get to evaluate which resource your opponent is lightest on (mana, threats, answers) and deny them access to it, on your way to eventually denying access to anything that matters at all