I don't have much to say about this one. It's a
kill spell. It's good. It hits quite a few
things in the current Standard format, though
not Bloodbraid Elf (but most of Jund's other
creatures), or Baneslayer Angel (but lots of
white weenie's creatures), or Ranger of Eos (but
the creatures he searched for) or Vampire
Nocturnus (but all of its minions). The "can't
be regenerated" clause won't come up much, but
the lack of a "nonblack" clause will be very
useful.
This is the kind of card I like to see in
Magic expansions (even though it's good against
my favorite creature River Boa). Playing with it
promotes smart deckbuilding, namely deciding
whether you're more afraid of cheap creatures or
expensive creatures. Playing against it promotes
smart deckbuilding, namely deciding how much
you're afraid of it and whether the extra mana
on (for example) Thieving Magpie as compared to
Shadowmage Infiltrator is worth it.
Today's card of the day is Smother which takes
a slightly different look at removal compared to
Black's other options. For the standard
two mana cost you can destroy target creature
with a converted mana cost of three or less
which would be most of the creatures that would
be in any deck design. Unlike most Black
removal this does work against any color making
it an excellent choice in or instead of using
the sideboard.
For Constructed, Casual, and Multiplayer almost
any Black deck will have some creature removal
and they are generally two mana. This is a
card that can easily be played in place of Doom
Blade or switched in when playing against Black
decks or regeneration.
With Limited a few removal spells are almost
always a worthwhile addition to the deck, but
the format does tend to promote a higher than
average number of four mana and higher creatures
which limits the usefulness a bit. In
Sealed it is removal cards that generally make a
Black pool seem appealing and it is definitely
worth playing any copies available. During a
Booster draft this should be one of if not the
first card picked from subsequent packs after
deciding to play Black.
Just be sure to have other options as this card
will be dead weight against any bigger threats
your opponent may play.