The forth deck in my series of explorations of the new Planeswalker signature spells revolves around Jace and his Ingenuity and Erasure. Jace's Erasure is obviously a "mill" card. I spent several days debating on weather to make this a W/U mill deck or a U/B mill deck. Obviously, Glimpse the Unthinkable and Mind Funeral are great mill cards that would compliment Jace's Erasure nicely. I have a playset of Glimpses that I've never really put to good use. The other idea was to reunite Jace with his Lorwyn Merrow bretheren. The merfolk in Lorwyn, the same set in which Jace made his debut, were themed around tapping for effects, with a more specific focus on milling effects. Jace's Erasure and the Planeswalker himself both fit quite nicely into that theme.
The benefit to running the Merrow over things like Glimpse the Unthinkable is that many of the Merrow provide reusable mill effects, such as the ones on Drowner of Secrets and Grimoire Theif. Stocking my deck with such repeatable effects lets me free up more card slots for defensive spells and other non-milling goodies. Going the Dimir route, I pretty much had to build the deck as aggressively mill-oriented as possible, basically going the Stupid Red Burn path of ignoring the opponent altogether and just pointing the best mill spell in hand at his dome every single turn until he dies or you do.
The other benefit to going W/U is that I thought the deck might actually function well in a multiplayer setting. At the very least it'd stand a much better chance than the U/B build. With the Dimir I could probably mill one guy out with relative ease, but I'd be completely out of steam by then, and the rest of the table could finish me off at their leisure. With cards like Judge of Currents and Silvergill Douser, I could stall and gain life, making me an unappealing target for any creature-reliant decks. I could also play politics with the Silvergill Douser, saving an opponent from attack in exchange for their not looking my way for the next turn or two.
Summon the School is a favorite card of mine, and plays nicely with a whole host of cards in the deck. Finally, there was a new card I wanted to try out - Shared Discovery. Drawing 3 cards for a single Blue mana is always a good deal. The drawback of Shared Discovery is that you must tap 4 creatures as part of the cost to cast it. In this deck, it's almost a benefit, rather than a drawback as the Merrow of Lorwyn LOVE being tapped.
I played the deck in a 5-way game without any countermagic and successfully milled everyone but the one guy playing a 100 card deck. And that was after the 100 card guy played a Time Spiral restocking everyone's libraries, and I got hit with a bout four Maelstrom Pulses, AND got hit buy an opponent's Jace's Ultimate ability, nuking 20 of my own cards! If I had been able to counter about 3 spells in that entire game - the Time Spiral, a timely Bogardan Hellkite, and any one of the many Maelstrom Pulses that hit me, I'd likely have been able to win the whole table.
So I added in a few counterspells. Namely, 2 Counterspell (with the Jace art from the J vs C Duel Decks) and 2 Forbid. Forbid is deliciously evil here, especially late game. With all the card draw it's fairly easy to find a couple of redundant cards to pitch, but the real amazing thing is to have two Summon the School in hand and 8 Merfolk on the Board. This is much easier than it looks, especially when you cast those Summons for a few turns, then just start holding them in hand with your Forbid. Someone tries to Wrath your board away, just pitch the Summons to Forbid, then tap your guys to get them back!
Enough talk, here's the decklist:
4 Hedron Crab
4 Judge of Currents
3 Silvergill Douser
2 Grimoire Thief
3 Drowner of Secrets
1 Lullmage Mentor
3 Shared Discovery
4 Jace's Erasure
2 Merrow Commerce
3 Jace Beleren
3 Summon the School
2 Jace's Ingenuity
4 Wanderwine Hub
3 Hallowed Fountain
1 Adarkar Wastes
2 Azorious Chancery
A few more notes. First, the Mana Base is basically whatever random W/B duals I could find laying around. I do recommend using as few enter-the-battlefield-tapped lands as possible, as it slows you down to much. Also, the Merrow Commerce are better than you'd think. There are lots of little tricks you can pull with two of them out, and they can speed up your milling process tremendously.
Lullmage Mentor is a one-of because it's strictly a late game card. if you NEED to cast him to get your Summon the School back, or get your Shared Discover online, fine, but if he doesn't hit the table with 7 Merfolk available and ready to go, he WILL die a grisly death. Late game, though, between him and the Forbids, no one will ever Wrath the board again, or Time Spiral for that matter. Those are really the only things you care about countering. Big creatures and the like should be no issue, between the Dousers and the Judges of Currents, your life total should be irrelevant. You just want to stop boardsweeps and library restockers, and anything else is just gravy.