It's a bit like the Living Weapon mechanic from the previous set, only you get a 2/2 counter instead of 0/0 counter
New standard cards were also revealed, showcasing the deep integration of Final Fantasy lore into MTG mechanics: Choco, Seeker of Shangri-La (from Final Fantasy 9): A powerful Chocobo Commander card, surprising even Ichikawa, who noted its historical parallels with Magic: The Gatherings Birds of Paradise
As for replacing Cyclonic Rift, you can go with Organic Extinction which will similarly clear the field of creatures
You can even negotiate a bit with Trap Essence since you dont have to put the counters on your own creature
Soul of the Harvest - draw engine for every creature you cast
My preference for Elspeth over Jace is down to fact that Elspeth will win games all on her own, Jace on the other hand just helps your deck to win more easily