This card does two very exciting things for a
very reasonable cost. First, it makes tokens.
Every turn you get another token. Remember
Bitterblossom? This is no Bitterblossom, because
the tokens have zero power, but getting one
every turn for no extra investment is a powerful
thing. They chump block, they build up, they
eventually contribute to the Overrun. And
second, it makes colorless mana. One extra mana
per turn it sticks on the board, in the form of
a sacrificeable creature. Granted, they're
one-time-use mana, and if you're using them for
creatures you likely don't want to have to sac
them for mana, but you have the option
available. This card gives you a steady stream
of resources that will only continue to
accumulate as the game progresses. The longer
the game goes, the more advantage you have if
this card is on the board.
It's a tribute (or condemnation) of
Bitterblossom's legacy that cards keep being
called "the [color] Bitterblossom." I think the
current holder for red is Goblin Assault, the
one for multicolor is Thopter Foundry, and the
one for blue is Sharding Sphinx. This is the
green one, but it's also an excellent synergist,
working overtime to bring the best out of
everything from Soul's Attendant to Polymorph.
Can Bitterblossom do that? (Don't say yes.)
Today's card of the day is Awakening Zone which
for only three mana puts a 0/1 Eldrazi Spawn
token into play on your turn. This would be a
good source of mana or blockers, but with the
set supporting the Spawn tokens they have
usefulness beyond mana and blocking.
In Limited the high cost of Eldrazi cards and
several support options make this card even
better and it is a worthwhile first choice in
Booster. For Sealed this can easily be played
alongside other Green options for acceleration
and make any high cost cards easier to play,
either by the blockers stalling the game or by
the added mana from sacrificing the tokens
directly.