They say any removal is good removal, and
colorless removal is in theory better, since
even Green and Blue (who struggle with that) can
use it. But seven mana to deal two damage, and
then four more mana every time you want to do it
again, or just be able to untap your creature?
And it doesn't even get around protection from
[color] like most colorless removal, since it's
the creature doing the damage instead of the
Arbalest itself, although you can equip it to a
colorless creature if you need to. The one that
first comes to mind is Soliton, since it can
untap itself on command and the two cards can
form a machine gun which basically allows you to
cast an infinite number of blue Shocks. But if
you don't have a combo like that, there's really
no reason to run a card like this.
Heavy Arbalest doesn't do anything that other
cards don't do, and it doesn't do those things
more efficiently than most of those cards. But
what it does offer is flexibility. Sometimes you
have a creature that can untap itself in some
way. Sometimes you'll have enough creatures that
you can keep handing the Arbalest around and
wipe out entire armies. Sometimes you'll just
have enough time to set up a creature with
deathtouch or lifelink and reap the benefits.
Sometimes you'll have a creature who wants to be
equipped as often as possible (Kemba?). Those
times, you might be glad to have a Heavy
Arbalest around.
Today's card of the day is Heavy Arbalest which
is a three mana equipment that costs four more
to actually equip making it far too costly for
just two damage as a tap effect. When you
add on the additional penalty this becomes a
card that is heavily penalized and is unlikely
to see any play outside of very casual decks.
Cards with untap effects do work well with this
and Soliton is in set, but the higher cost of
both makes it a slow combo compared to older
versions. Overall a weak card that can be
used in combination with other cards, but is
just a bit too slow to really be worth the
effort.
In Limited the cost may seem somewhat elevated,
but the format is slower and removal options
aren't as readily available so this is playable.
Not as high of a pick as other choices, but
still worth using and works far better than it
would in a Constructed format. As an
artifact it fits in well for any deck, counts
for Metalcraft, and works well with Infect
creatures.