If you do, target player loses 2 life and you gain 2 life
Well, because we can take their counterspell or removal spell for our threat for one mana and resolve our threat instead of spending a bunch of mana each turn to try to resolve a spell
While I think that Terra, Herald of Hope is an interesting commander, I think that this version is a much better representation of who Terra is and what she can do
Having access to Green Sun's Zenith could also help power up decks like Elves, which could certainly use the help, and maybe even allow for something similar to Maverick (a creature-heavy Gx midrange deck) to develop in the format
I really like this stuff, because the combination of burn and removal, along with solid creatures give a powerful base to win the game with
While Magic: the Gathering cant replicate this exactly, the designers were clearly inspired by Terras journey while developing her Commander deck