If you'd like further reading on some of the common arguments (and why they're incorrect), Patrick Chapin wrote a great article on this very subject that you can read here
Calgar's ability is also better for getting cards than Greyfax's, as you don't need to faff around with getting a Clue token and paying even more to sacrifice it Calgar just gives you a draw instead
Alternatively, you can turn your ex-oriented Water deck into a bit of a one-point deck by consistently resurrecting and playing a Manaphy
Waterfront Bouncer (Masques/Nemesis/Prophecy) The best non-rare Spellshaper, Waterfront Bouncer was perhaps the most powerful common in the format in and of itself
That may sound narrow, but its amazing for grabbing utility creatures like Mother of Runes, Esper Sentinel, or anything else that gives you cheap power or combo potential
It's not just Avengers-slash-Magic, right