MTG Salvation

Well damn that word is bad ass

To be honest this really calls out to me a comparison to another dangerous blue creature.

Teferi, Mage of Zhalfir:
2UUU (cheap but color intensive)
3/4 (meh, not a bad blocker)
Flash (cast time flexibility. assists assuring he lives)
Creature cards you own that aren't on the battlefield have flash. (flexibility for your creature spells, second reason he's played)
Each opponent can cast spells only any time he or she could cast a sorcery. (limiting opponents' play options. main reason he is played)

Sphinx of the Final Word:
5UU (expensive but less color intensive)
5/5 (ok)
Sphinx of the Final Word can't be countered. (pro. from blue mages, except time stop and venser, shaper savant)
Flying, Hexproof (Evasion & pro. from single target removal)
Instant and sorcery spells you control can't be countered by spells or abilities. (pro. from blue mages for your spells)

Specific comparison on their last abilities:
Teferi, Mage of Zhalfir - his ability pretty much means you control the stack, since you are the only one that can respond to spells. This ability is crueler and wider control of the game.

Sphinx of the Last Word - when I think about it now, it seems that this ability is comparable to Teferi's giving your creatures flash, only it secures your instants & sorceries. If you have counterspells and mana, you still have good control on the stack, only not quite as extensive as Teferi's.

TLDR: Teferi is cheaper (although color intensive), and has the superior ability, yet has a weaker body. Sphinx is more expensive and not quite as controlling, yet is harder to remove and has the better body.

I guess Teferi is still better, but I'm sure that EDH decks that are looking for redundancy or replacement with him will still be delighted to add this card to their ranks.

HEXPROOF

Ramp him out turn 4 GAME OVER.... WORD