At the beginning of combat on your turn, if you control two or more other legendary creatures, you may transform Serah Farron
While WotC has demonstrated theyre willing to fast track reprints of popular and/or expensive cards from these sets, these booster boxes have a lot more going for them than against in the long run so long as they remain at or under $100 a box
It will remain part of the rotation for Standard for at least a few years, but even once it does, youll still be able to play the cards in formats like Modern (which uses any card released since the 8th edition of Magic began in 2003, including the sets that are still in the Standard rotation)
Able to grab the best card for any situation from your sideboard, if you have a Karn on the field, you're prepared for anything
These can help you combat cards like Back to Basics and Ruination and give you something to fetch if you get targeted by Ghost Quarter
I dont care much for Cass, Hand of Vengeance