I think its about right actually.
Granted the squid combo is nasty, but squids are quite weak and vulnerable...
Combining this with SoP squids could be very potent though...
Still thats several cards to combo in a deck and counters to it would abound.
(kill squids, eternity / rewind, destroy /steal SoP, lobo squids, quanta denial, voodoo dolls, immaterial based decks, etc)
Given the fairly high burst damage potential (3 damage to all frozen unupped or 4 upped) I think a small cost bump might be warranted.
All in all though I like this card... though I could swear I've seen something similar proposed before... frostbite or something like that.
Anyway, nicely done!
-PS: Does the effect stack? Clearly the initial damage will, but what about the damage over time? This will be quite significant.