The advantage of plotting Step Between Worlds is being able to cast it for free later on, freeing up all your mana for the seven new cards you draw.
It provides incredible ramp for a Grixis deck
The ability to drop two of these and just sac all your permanents to a Ravager at any given point for the win was the norm
Its not quite there, but its the first fancy version of this blue sorcery, only being printed in Conspiracy: Take the Crown and Mystery Booster so far, so I expect this to be a good chunk more than that base price
However, if instead the creature's power is increased to 4 or greater after the ability resolves, it still can't be blocked that turn
Release date: 2022-09-21 And They Shall Know No Fear Celestine, the Living Saint Defenders of Humanity For the Emperor