I've long maintained that if Sensei's Divining
Top was banned for time-wasting concerns, the
same scrutiny should be applied to fetchlands. I
mean, everybody wants Steppe Lynx to be good,
but have you ever timed just how long it takes
for a deck with ten fetchlands (that's one-sixth
of its cards) to be sufficiently randomized each
time? Even if somehow the time issue wasn't
significant, Sensei's Divining Top would have
been problematic. One of the things that makes
Brainstorm insane is the ability to legally
stack the top of your deck. Now do so every
turn. On an artifact. That isn't susceptible to
targeted artifact removal. Unlike yesterday's
card, it's hard to think of a way to use the Top
"fairly", although I admit my memories of the
Winterbalance deck from Kamigawa-Ravnica
Standard might be getting in the way!
The Kamigawa block has a reputation for being
bad, but I don't think it's an entirely fair
reputation, particularly with Champions of
Kamigawa. The first set of the block had some
especially nasty cards that would go on to be
the linchpin of several decks, and Sensei’s
Divining Top is definitely one of those cards.
The effect seems innocuous enough, but it's
anything but innocuous. In conjunction with
fetchlands, the Top lets you maximize the
efficacy of your fetches. And paired with
Counterbalance (from Coldsnap), the little
artifact can make it almost impossible for your
opponents to resolve a spell ever again. It's a
staple of Legacy in decks such as Miracles
(thanks to how it interacts with the Miracle
spells from Avacyn Restored), and it's rightly
an EDH staple because of its splashability, its
potent effect, and its ability to drive your
opponents up a wall with repeated uses.
Also, in conjunction with untap effects, the Top
lets you draw a lot of cards from the top of
your library with minimal cost to you. For a
1-mana artifact, Sensei's Divining Top is an
excellent card, and all but the most aggressive
decks will find its effects at least usable.