Balance does not simply happen overnight when it comes to strategy
games.  Even your team of expert designers who have worked on
other successful strategy games cannot predict everything will go as
planned when it comes to strategies, and how units actually play out
against each other.  StarCraft II is not exempt from this even
with its massive development cycle.  Since hitting beta, the
game has all but turned upside down from a unit and stat based
perspective, and we’re here to show you just how your favorite strategy
came to exist today.

href="http://www.tentonhammer.com/node/87023"> src="http://www.tentonhammer.com/image/view/87023"
style="border: 2px solid ; width: 300px; height: 300px;">

style="font-style: italic;">Just when you thought the one
staple unit of Zerg would be left alone... they increase the cost of
Overlord Speed.

Terran Evolution

The early days were good for Terran.  Reapers were, plain and
simple, almost untouchable.  They did more damage to
buildings, built quicker, and Nitro Packs researched in no
time.   If those failed, you could switch to Reactors
and pump out Marines at a dangerous speed.  Ghosts could
pretty much disable a whole Protoss army in one EMP.



Slowly the nerf hammer fell. Reapers became a more risky opener with a
much larger build time.  Marines build slower, and the
reactor’s build time was doubled, destroying early mass infantry builds
completely.  To balance these nerfs, Ghosts were made cheaper
gas-wise and all research for infantry has fallen in price since the
beta started.  No longer is researching one ability a symbol
of going all-in on the unit due to costs and time involved.



Thors have been all over the place.  From worthwhile to
worthless, and back in the other direction once more, the Thor now
attacks faster while doing less damage, and has a smaller
footprint.  They then changed its anti-air attack to deal
splash damage, absolutely destroying clusters of light air. 
Combine that with the turret change that makes them do standard damage
against all types of flyers and you have the end of Mutalisks for
Terran to deal with usually.



Air has been tinkered with a lot less, and across the board you’ll see
reduced build times and easier access to the abilities and power that
makes Terran air work.  Cost reductions, HP increases, and
flat out removal of prerequisites really help the Terran air
game.  Unfortunately, all of these buffs came with one big
nerf--the SCV only has 45 HP now.  Worker harassment is much
more dangerous early on for Terran with this in place.

Zerg Evolution

The Zerg are touched much less than the other races, but generally hit
harder by buffs and nerfs each time they happen.  Hidden buffs
such as AI improvements for surrounding and moving around large
clusters of units greatly enhances Zerglings, despite having the exact
same stats as their previous incarnation in the original game.



Roaches... where to begin?   They started off having
the 2nd highest base armor in the game, costing a tiny amount and
regenerating a silly amount of HP while underground. 
Complaints and balance slowly forced the Roach into a more standard
unit--1 armor, much less regeneration underground, anemic movement
speed and ‘might as well not even move at all while underground’
speed.  On top of that, they’re now 2 supply each instead of
1--a decisive blow, and reason enough not to use many in the mid/late
game phase.



Hydralisks and Brood Lords have been hit hard.  The difference
is one of these units is still viable.  Hydralisks remain one
of the most threatening units in the game, and now are one of the most
fragile units in the game at 80 HP.  Meanwhile, Broodlords
have lost a third of their damage, a quarter of their HP, some armor,
and might as well not exist anymore.  What was a viable late
siege unit is now a flying waste of resources in almost every situation.



The Ultralisk gets special mention for having the other races basically
balanced around it at this point.  It’s a titan of the
battlefield, and is an easy target for everything.  Thors
loved to dump their big cannons on them, and most notably, mind control
from the Infestor removes the Ultralisk as a threat
completely.  So they introduced a new skill to make target
units immune to that, and that didn’t fly.  This is
StarCraft.  Units die in a fraction of a second so there is no
time to put buffs on units!  So that was taken out, Infestors
and Thors both now have to research their big unit counters, and the
Ultralisk has its base movement speed increased to its upgraded level
and the upgrade removed.  On top of that, they’ve made it an
anti-armor unit!  This makes it the only other unit besides
the Spine Crawler that has a bonus against Armored in the Zerg arsenal.

Protoss
Evolution

Tinkering with the Zealot was inevitable.  It’s a powerhouse
of a unit, the first unit that comes out, and inevitably, people rushed
with them.  However, only losing 10 shields on the unit and
then having it left alone means that the Zealot was never that
all-powerful to begin with.  You can still Zealot rush and
win, only now you just have to be a little bit more careful.



Stalkers used to be pathetic anti air.  A Mutalisk would kill
a Stalker 1v1 almost, since their attack was designed to be hard
anti-armor.  They now maintain a slight armored bonus, but
deal more damage to all target types instead.  Meanwhile, the
Mothership took a series of heavy nerfs and is pretty much never seen,
both due to this and its placement in the tech tree.



Both forms of Templar have taken heavy nerfs.  High Templar’s
Psi Storm now has a rather small area of effect, making it difficult to
get the full damage on anyone that is awake.  Dark Templar
rushing was viable in some situations, but a combination of cost
increase and build time on the Dark Shrine has pretty much negated the
most vulnerable period to strike.  It takes as long to warp in
one of those as it does a new nexus!



Perhaps the biggest change is seen in the basic air units. 
The Void Ray started off as a medium attacker that had 3 levels of
charge.  Now it’s more fragile, more expensive, and only has
one new level of damage and less range.  No longer is it a
fighter, it’s more like a strategic bomber on key targets before it
gets shot down.  There is no need for it shooting air units
with the new Phoenixes around though.  Nothing has changed
about them except, for the first time in a Blizzard RTS, a unit can
attack while moving.  This is mind-blowing and can give your
Phoenixes, already the fastest unit in the skies, an edge on any
pursuers by firing as they retreat.