<s>
StarCraft	B-Application
II	I-Application
:	I-Application
Heart	I-Application
of	I-Application
the	I-Application
Swarm	I-Application
is	O
an	O
expansion	O
pack	O
to	O
the	O
military	O
science	O
fiction	O
real-time	O
strategy	O
game	O
StarCraft	B-Application
II	I-Application
:	I-Application
Wings	I-Application
of	I-Application
Liberty	I-Application
,	O
and	O
the	O
second	O
part	O
of	O
the	O
StarCraft	B-Application
II	I-Application
trilogy	O
developed	O
by	O
Blizzard	O
Entertainment	O
,	O
with	O
the	O
final	O
part	O
being	O
Legacy	B-Application
of	I-Application
the	I-Application
Void	I-Application
.	O
</s>
<s>
The	O
expansion	O
includes	O
additional	O
units	O
and	O
multiplayer	O
changes	O
from	O
Wings	B-Application
of	I-Application
Liberty	I-Application
,	O
as	O
well	O
as	O
a	O
continuing	O
campaign	O
focusing	O
on	O
the	O
Zerg	O
race	O
and	O
following	O
Sarah	O
Kerrigan	O
in	O
her	O
effort	O
to	O
regain	O
control	O
of	O
the	O
swarm	O
and	O
exact	O
her	O
revenge	O
on	O
the	O
Terran	O
Dominion	O
's	O
emperor	O
,	O
Arcturus	O
Mengsk	O
.	O
</s>
<s>
During	O
BlizzCon	O
2017	O
,	O
Blizzard	O
announced	O
that	O
StarCraft	B-Application
II	I-Application
would	O
be	O
re-branded	O
as	O
a	O
free-to-play	O
game	O
,	O
hence	O
opening	O
the	O
multiplayer	O
mode	O
to	O
everybody	O
and	O
bringing	O
some	O
changes	O
to	O
previously	O
paid	O
features	O
of	O
the	O
game	O
.	O
</s>
<s>
The	O
Wings	B-Application
of	I-Application
Liberty	I-Application
campaign	O
was	O
made	O
completely	O
free	O
while	O
the	O
campaigns	O
for	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
and	O
Legacy	B-Application
of	I-Application
the	I-Application
Void	I-Application
still	O
required	O
payment	O
.	O
</s>
<s>
However	O
,	O
those	O
who	O
had	O
already	O
bought	O
Wings	B-Application
of	I-Application
Liberty	I-Application
before	O
the	O
free-to-play	O
announcement	O
were	O
granted	O
access	O
to	O
the	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
campaign	O
free	O
of	O
charge	O
.	O
</s>
<s>
Micro-transactions	O
such	O
as	O
Skins	O
,	O
Co-op	O
Commanders	O
,	O
Voice	O
Packs	O
,	O
and	O
the	O
War	O
Chests	O
proved	O
to	O
be	O
successful	O
enough	O
to	O
sustain	O
StarCraft	B-Application
II	I-Application
as	O
a	O
story-driven	O
and	O
eSport	O
title	O
.	O
</s>
<s>
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
features	O
a	O
single-player	O
campaign	O
with	O
20	O
missions	O
(	O
plus	O
seven	O
evolution	O
missions	O
which	O
allow	O
the	O
player	O
to	O
upgrade	O
units	O
)	O
,	O
and	O
continues	O
the	O
story	O
from	O
Wings	B-Application
of	I-Application
Liberty	I-Application
.	O
</s>
<s>
Similar	O
to	O
Wings	B-Application
of	I-Application
Liberty	I-Application
,	O
the	O
briefing	O
room	O
allows	O
interactive	O
exploration	O
,	O
this	O
time	O
on	O
the	O
Leviathan	O
,	O
an	O
enormous	O
Zerg	O
breed	O
which	O
functions	O
as	O
a	O
bioship	O
.	O
</s>
<s>
At	O
BlizzCon	O
2011	O
,	O
it	O
was	O
revealed	O
that	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
would	O
feature	O
seven	O
new	O
multiplayer	O
units	O
,	O
while	O
removing	O
three	O
units	O
and	O
changing	O
the	O
abilities	O
of	O
existing	O
units	O
and	O
buildings	O
.	O
</s>
<s>
Several	O
Terran	O
units	O
were	O
modified	O
in	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
.	O
</s>
<s>
The	O
Hellbat	O
counts	O
as	O
both	O
biological	O
and	O
mechanical	O
,	O
and	O
can	O
therefore	O
be	O
either	O
repaired	O
by	O
SCVs	O
or	O
healed	O
by	O
Medivacs	O
and	O
Medics	B-Application
.	O
</s>
<s>
Additionally	O
,	O
it	O
no	O
longer	O
needs	O
a	O
Tech	O
Lab	O
add-on	O
to	O
be	O
produced	O
,	O
allowing	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
players	O
to	O
train	O
two	O
of	O
them	O
at	O
a	O
time	O
using	O
the	O
Reactor	O
add-on	O
.	O
</s>
<s>
The	O
Tempest	O
is	O
a	O
large	O
,	O
slow	O
flying	O
unit	O
that	O
was	O
originally	O
developed	O
in	O
the	O
Wings	B-Application
of	I-Application
Liberty	I-Application
beta	O
as	O
a	O
replacement	O
for	O
Carriers	O
.	O
</s>
<s>
(	O
Blizzard	O
have	O
tried	O
to	O
remove	O
Carriers	O
from	O
the	O
game	O
before	O
both	O
StarCraft	B-Application
II	I-Application
releases	O
,	O
only	O
to	O
put	O
them	O
back	O
in	O
due	O
to	O
overwhelming	O
fan	O
demand	O
.	O
)	O
</s>
<s>
After	O
Wings	B-Application
of	I-Application
Liberty	I-Application
,	O
in	O
which	O
it	O
functioned	O
basically	O
like	O
a	O
Carrier	O
,	O
it	O
was	O
revised	O
in	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
to	O
provide	O
large	O
amounts	O
of	O
aerial	O
splash	O
damage	O
,	O
and	O
then	O
again	O
to	O
do	O
extra	O
damage	O
to	O
Massive	O
units	O
.	O
</s>
<s>
The	O
Hydralisk	O
has	O
regained	O
its	O
speed	O
boost	O
upgrade	O
from	O
Brood	B-Application
War	I-Application
.	O
</s>
<s>
In	O
addition	O
,	O
there	O
are	O
"	O
primal	O
"	O
versions	O
which	O
are	O
elements	O
of	O
the	O
plot	O
and	O
sport	O
a	O
radically	O
different	O
look	O
(	O
the	O
differences	O
are	O
akin	O
to	O
those	O
between	O
regular	O
and	O
mercenary	O
units	O
in	O
Wings	B-Application
of	I-Application
Liberty	I-Application
)	O
.	O
</s>
<s>
Following	O
the	O
events	O
of	O
Wings	B-Application
of	I-Application
Liberty	I-Application
,	O
Terran	O
Dominion	O
forces	O
attack	O
Sarah	O
Kerrigan	O
and	O
her	O
allies	O
in	O
a	O
research	O
facility	O
in	O
the	O
territory	O
of	O
the	O
Umojan	O
Protectorate	O
.	O
</s>
<s>
The	O
development	O
of	O
StarCraft	B-Application
II	I-Application
was	O
announced	O
on	O
May	O
19	O
,	O
2007	O
,	O
at	O
the	O
Blizzard	O
Worldwide	O
Invitational	O
in	O
Seoul	O
,	O
South	O
Korea	O
.	O
</s>
<s>
At	O
the	O
June	O
2008	O
Blizzard	O
Worldwide	O
Invitational	O
,	O
Blizzard	O
Executive	O
Vice	O
President	O
Rob	O
Pardo	O
said	O
that	O
StarCraft	B-Application
II	I-Application
was	O
to	O
be	O
released	O
as	O
a	O
trilogy	O
of	O
games	O
,	O
starting	O
with	O
Wings	B-Application
of	I-Application
Liberty	I-Application
,	O
focused	O
on	O
the	O
Terrans	O
,	O
followed	O
by	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
,	O
revolving	O
around	O
the	O
Zerg	O
,	O
and	O
finally	O
Legacy	B-Application
of	I-Application
the	I-Application
Void	I-Application
,	O
devoted	O
to	O
the	O
Protoss	O
.	O
</s>
<s>
Blizzard	O
's	O
storyboard	O
team	O
was	O
already	O
working	O
on	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
in	O
early	O
2010	O
while	O
Wings	O
of	O
Libertys	O
gameplay	O
was	O
refined	O
.	O
</s>
<s>
Wings	B-Application
of	I-Application
Liberty	I-Application
was	O
released	O
July	O
27	O
,	O
2010	O
to	O
much	O
critical	O
acclaim	O
.	O
</s>
<s>
However	O
,	O
the	O
expansion	O
will	O
have	O
the	O
same	O
hardware	O
requirements	O
as	O
Wings	B-Application
of	I-Application
Liberty	I-Application
.	O
</s>
<s>
On	O
April	O
30	O
,	O
2012	O
,	O
Blizzard	O
announced	O
that	O
the	O
latest	O
multiplayer	O
build	O
of	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
would	O
be	O
playable	O
at	O
the	O
MLG	O
Spring	O
Championship	O
(	O
June	O
8	O
–	O
10	O
)	O
ahead	O
of	O
a	O
planned	O
beta	O
release	O
.	O
</s>
<s>
The	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
beta	O
closed	O
on	O
March	O
1	O
,	O
2013	O
.	O
</s>
<s>
Blizzard	O
officially	O
released	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
for	O
PC	O
and	O
Mac	O
systems	O
in	O
multiple	O
countries	O
on	O
March	O
12	O
,	O
2013	O
.	O
</s>
<s>
StarCraft	B-Application
II	I-Application
:	I-Application
Heart	I-Application
of	I-Application
the	I-Application
Swarm	I-Application
sold	O
approximately	O
1.1	O
million	O
copies	O
worldwide	O
in	O
its	O
first	O
two	O
days	O
on	O
sale	O
,	O
and	O
was	O
the	O
top-selling	O
PC	O
game	O
for	O
the	O
first	O
quarter	O
of	O
2013	O
.	O
</s>
<s>
StarCraft	B-Application
II	I-Application
:	I-Application
Heart	I-Application
of	I-Application
the	I-Application
Swarm	I-Application
received	O
"	O
generally	O
favorable	O
reviews	O
"	O
from	O
critics	O
according	O
to	O
review	O
aggregator	O
Metacritic	O
.	O
</s>
<s>
The	O
cinematics	O
from	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
received	O
the	O
2013	O
Golden	O
Reel	O
Award	O
for	O
Best	O
Sound	O
&	O
Music	O
Editing	O
:	O
Computer	O
Interactive	O
Entertainment	O
from	O
the	O
Motion	O
Picture	O
Sound	O
Editors	O
society	O
.	O
</s>
<s>
In	O
addition	O
to	O
the	O
standard	O
game	O
,	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
is	O
offered	O
in	O
two	O
special	O
variants	O
for	O
purchase	O
:	O
Digital	O
Deluxe	O
and	O
Collector	O
's	O
Edition	O
.	O
</s>
<s>
DVD	O
versions	O
of	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
require	O
an	O
additional	O
content	O
download	O
of	O
approximately	O
8	O
gigabytes	O
of	O
data	O
before	O
the	O
game	O
can	O
be	O
played	O
for	O
the	O
first	O
time	O
.	O
</s>
<s>
The	O
soundtrack	O
for	O
Heart	B-Application
of	I-Application
the	I-Application
Swarm	I-Application
was	O
released	O
in	O
two	O
volumes	O
.	O
</s>
<s>
The	O
release	O
of	O
the	O
expansion	O
saw	O
a	O
short-term	O
renewal	O
of	O
interest	O
in	O
StarCraft	B-Application
II	I-Application
's	O
competitive	O
multiplayer	O
scene	O
and	O
brought	O
about	O
the	O
standardization	O
of	O
competition	O
by	O
Blizzard	O
Entertainment	O
through	O
the	O
redesigned	O
StarCraft	B-Application
II	I-Application
World	O
Championship	O
Series	O
,	O
but	O
saw	O
a	O
long-term	O
decline	O
in	O
interest	O
,	O
sponsorship	O
,	O
and	O
viewership	O
.	O
</s>
<s>
Following	O
the	O
transition	O
of	O
the	O
title	O
to	O
free-to-play	O
two	O
years	O
after	O
the	O
release	O
of	O
Legacy	B-Application
of	I-Application
the	I-Application
Void	I-Application
,	O
the	O
second	O
and	O
final	O
StarCraft	B-Application
II	I-Application
expansion	O
,	O
the	O
game	O
has	O
experienced	O
a	O
resurgence	O
in	O
interest	O
.	O
</s>
