This is no longer a shell, and it works! I would love to add the new fetchlands to it and see it go off turns 4 and 5 every time.
Here is a game in which I show how Gifts Ungiven works. I started with a God hand, and this is very rarely the case.
I place two fatties in my graveyard.
I place one on the battlefield by hard-casting Unburial Rites as a 5-drop.
Here is my fattie on the battlefield.
Notice that the Flashback cost for Unburial Rites is 4 mana. Cards with
Flashback cost more to Flashback than to hard cast, and this one card
has the opposite set-up.
And here is my second fattie on the battlefield. At this point my opponent gave up.
And here is a game against RDW. If I can land the whale, its gg because my opponent cannot attack with creatures. A single Gifts Ungiven is so effective that even Snapcaster Mage becomes a supporting card!