It seems to me that a 3 CMC instant that simply gave all your creatures protection from all colors unconditionally unitl the end of the turn still wouldn't be very good. Sure: this card was meant to showcase the set's domain theme, but making the card weak for the mana even when fully supported doesn't seem like a good way of going about doing that.
Posted By:
scumbling1
(5/31/2011 3:50:55 PM)
I play this in some five color commander decks for its versatility. It makes annoying auras fall off, makes my guys virtually unblockable, counters targeted spells or abilities, makes your creatures win combat if you are on the defense, and prevents global damage. For three mana that is pretty neat.
Posted By:
majinara
(8/22/2011 3:08:34 PM)
My new favorite 'Protection' card in White, short of the Circles themselves! :D
Idkn if it's the Spikiest, but it looks like it has maybe the most *potential*
Posted By:
DarthParallax
(6/21/2012 4:47:13 AM)
While not worth splashing four colors for, it does good work in five color decks.
People don't seem to get that you don't play 5 color for an effect like this, it's just a bonus for a deck that was already five color.
Posted By:
TPmanW
(5/1/2013 10:12:48 PM)
Should have been 
since it's quite a task to make this reliable.
But between Prismatic Omen and Nylea's Presence, this might find some use in Domain decks.
Posted By:
Mode
(6/2/2014 1:55:02 AM)