Rona untaps itself whenever you cast a legendary creature, and can tap to loot
Apart from fringe cases like Grim Tutor, they are all tried and tested in formats past, and we can assume that Wizards is including them here because the gameplay they created there is of a sort that the creators of the game want to see in the next few years of Standard
The back face of each card is designed to be compatible with standard Magic sleeves, making them a great option for collectors and players alike
It could also mean a new type of card or item that can be equipped to a character like Armor or a weapon
The Great Henge is a bit like [c]Beast Whisperer[/c] in that you draw a card each time you play a creature
In case you missed it, Final Fantasys Magic: The Gathering set was, as Ron Burgundy might put it, kind of a big deal