If you wished, you could see this card's text as
having the word "dragon" added just to emphasize
Dragons of Tarkir's theme; but I actually don't
mind that so much. I kind of like when cards are
designed to interact with different cards, or
different classes of cards, because it makes
things seem more unique and less
interchangeable. You can certainly use this as a
generic Cruel Edict effect in those dragon-based
control decks that I understand see play in
Standard sometimes, but it also fits in more
casual theme decks and can be played in limited,
even if you weren't lucky enough to get a
suitable dragon to go with it.
Today's card of the day is Foul-Tongue
Invocation which is a three mana Black instant
that has a player sacrifice a creature and if
you reveal a dragon card you gain four life.
There have been multiple similar cards over the
years with Tribute to Hunger probably the
closest and in a deck with dragons or Changeling
cards this is often better. A potential
four life instead of a likely one to three is
nice, though while this can be better it is more
situational and only belongs in certain theme
decks or formats where options are more limited.
Definitely playable and another weapon in
Commander or Standard, but other options exist
for Modern and older formats.
In Limited this is an excellent low cost removal
option that is a clear second pick in Booster
after a Black rare or a first choice in a weak
pack. In Sealed this can encourage
splashing Black or playing the color outright
and the potential life gain adds value with any
dragons in the primary color.