Once it enters, you can move any characters you control to one location - this is great for avoiding paying costs , but it comes with another bonus
Note that you can also use discard/surveil effects to set up reanimator lines with this
Use the total mana value of other permanents you control as Summon: Bahamut's fourth chapter ability resolves to determine how much damage is dealt
I dont think it matters much in the long term, as these are fantastic cards with iconic characters and for something as universal as Rift, it doesnt matter whats on the art
Of course, they could exert for other reasons and avoid having to challenge, but if you can get something big enough of your own exerted, your opponents characters will crash against it and take themselves out
While not particularly powerful, Winnie the Pooh Hunny Wizard typically sells for around $200