Even if you're using cost to compensate for it not being a shield, spell damage still a very narrow niche to protect from. Chances are most people would still run Jade or Reflective Shield for better damage reduction/much cheaper cost. I can understand the upgraded version being expensive but making it unprotectable is a bit silly given that both Relflective Shields start out immaterial.
I'd suggest lowering the unupped spell's cost a bit (you'd really only need to give a massive cost raise to a permanent with a shield property) and removing the "Unprotectable" from the upped permanent version.
So, unnupped cost of maybe... 3? And the upped stays the same..?
The unupped in general is a very UP card, as of unless you chain them, the opponent can just wait another turn to Firebolt you to death (among other things). So basically it's a more expensive and less useful Silence.
I think the card could really be put at 1
and given an extra effect and not be OP at all. I would suggest "draw a card", but Time already has Precog..
Perhaps maybe also lets your spells deal double damage that turn? Although that might warrant a two
cost.
