There are more powerful counterspells, but a 3-mana counterspell that matches your decks major creature type is more fun
While it's fun to play and to brew - with all sorts of different combos and win cons you can try out, some people complain that Nadu is tedious to play against
Players sometimes justify its inclusion through logic such as "If you mill six cards from your own deck, and the only flashback card that you turn over is a Think Twice, you're still going to be even on cards." But in green-blue-black mill-yourself decks that are actively looking to get as much of their library as possible (and in some cases all of it) into their graveyard, finding ways to continue to mill yourself is absolutely crucial
Aclazotz, Deepest Betrayal Aclazotz, Deepest Betrayal is a 4/4 with flying and lifelink, and when it attacks, your opponents discard a card, or else you draw a card for everyone that cant
Mark Rosewater has mentioned it sits at about a 7 on the Storm Scale, which means that it's unlikely it'll return even if it's not impossible
Savage Swipe is not only excellent thanks to the large number of good two power creatures, it benefits from the dearth of instant speed interaction
