This is a fantastic example of a card that really feels like it needs the restriction of only being activated once per turn
You can use it to ramp yourself via Fetchlands, double down on powerful enters or leaves abilities, and everything in between
It is not the absolute top card of the set, but it is consistently one of the most asked-about cards and one of the harder slots to fill in a master set
And that hasnt ended, we just flavor stuff after planeswalkers (Jace's Erasure, Liliana's Specter, Chandra's Ignition) or still after legendary creatures (Ezuri's Predation, Daxos's Torment, Kalemne's Captain, Gisa's Bidding, Geralf's Masterpiece, Oona's Grace, etc)
A pair of 3/3 creature tokens whenever you commit your first crime each turn is jawdropping, tapped or not
If this happens, the price of Equinox could absolutely skyrocket since there are so few copies available