For your interest, this is a reworked version
of Draining Whelk, from Time Spiral. Considering
how easy color fixing is in Ravnica, you can
consider being two colors an advantage over its
ancestor, in a sort of roundabout way, as it
gives you access to a whole different set of
creatures and spells. Either way, this version
is good at closing out games in control decks,
with the fact that it's a spell and not a
creature giving you the relevant bonuses from
cards like Talrand and Lunar Mystic. Not to
mention that Oozes are always popular.
Today's card of the day is Mystic Genesis which
is a five mana Blue and Green that counters
target spell and puts an X/X Green ooze token
into play where X equals the converted mana cost
of the countered spell. A five mana counterspell
is a bit too expensive for competitive formats
and the token, while adding card advantage, it
too often will not be a large enough creature to
justify the cost and keeping that much mana
untapped. Overall it isn't exactly a bad card,
just not practical, despite being efficient, and
isn't likely to see much play.
For Limited this is a decent potential
trigger for Evolve and some card advantage which
can even be a bit of a threat if used against a
higher cost spell. There's no reason not to play
this in a Simic deck when opened in Sealed and
is strong enough to be a first pick in Booster,
even though it may not be as directly impressive
as other Simic rares.