<s>
It	O
was	O
originally	O
released	O
in	O
1998	B-Application
for	O
the	O
Neo-Geo	B-Application
MVS	I-Application
arcade	O
platform	O
as	O
the	O
sequel	O
to	O
the	O
1996	O
game	O
Metal	B-Application
Slug	I-Application
.	O
</s>
<s>
The	O
original	O
version	O
of	O
the	O
game	O
had	O
extensive	O
slowdown	O
and	O
performance	O
issues	O
,	O
eventually	O
leading	O
SNK	O
to	O
release	O
a	O
modified	O
version	O
in	O
1999	B-Application
titled	O
.	O
</s>
<s>
It	O
has	O
been	O
ported	O
to	O
the	O
Neo	B-Device
Geo	I-Device
CD	I-Device
,	O
PlayStation	B-Device
,	O
Virtual	B-Application
Console	I-Application
,	O
iOS	B-Application
and	O
Android	B-Application
,	O
and	O
to	O
the	B-Operating_System
Wii	I-Operating_System
,	O
PlayStation	B-Operating_System
Portable	I-Operating_System
and	O
PlayStation	B-Device
2	I-Device
(	O
as	O
part	O
of	O
the	O
Metal	B-Application
Slug	I-Application
Anthology	I-Application
)	O
.	O
</s>
<s>
The	O
game	O
added	O
several	O
new	O
features	O
to	O
the	O
gameplay	O
of	O
the	O
original	O
Metal	B-Application
Slug	I-Application
,	O
such	O
as	O
new	O
weapons	O
,	O
vehicles	O
and	O
the	O
ability	O
to	O
transform	O
the	O
character	O
.	O
</s>
<s>
It	O
was	O
followed	O
by	O
Metal	B-Application
Slug	I-Application
3	I-Application
released	O
in	O
2000	O
.	O
</s>
<s>
Gameplay	O
in	O
Metal	B-Application
Slug	I-Application
2	I-Application
is	O
similar	O
to	O
the	O
previous	O
game	O
;	O
the	O
player	O
must	O
shoot	O
constantly	O
at	O
a	O
continual	O
stream	O
of	O
enemies	O
in	O
order	O
to	O
reach	O
the	O
end	O
of	O
each	O
level	O
.	O
</s>
<s>
On	O
the	O
way	O
through	O
each	O
level	O
,	O
the	O
player	O
can	O
find	O
numerous	O
weapon	O
upgrades	O
and	O
"	O
Metal	B-Application
Slug	I-Application
"	O
tanks	O
.	O
</s>
<s>
Metal	B-Application
Slug	I-Application
2	I-Application
introduces	O
the	O
ability	O
for	O
characters	O
to	O
transform	O
during	O
the	O
course	O
of	O
the	O
game	O
.	O
</s>
<s>
As	O
well	O
as	O
doubling	O
the	O
number	O
of	O
available	O
player	O
characters	O
from	O
two	O
to	O
four	O
,	O
Metal	B-Application
Slug	I-Application
2	I-Application
introduces	O
in-game	O
characters	O
to	O
help	O
the	O
player	O
in	O
battle	O
.	O
</s>
<s>
Two	O
years	O
have	O
passed	O
since	O
the	O
end	O
of	O
Metal	B-Application
Slug	I-Application
,	O
when	O
Capt	O
.	O
</s>
<s>
An	O
upgraded	O
version	O
of	O
Metal	B-Application
Slug	I-Application
2	I-Application
,	O
titled	O
Metal	B-Application
Slug	I-Application
X	O
,	O
was	O
released	O
in	O
March	O
1999	B-Application
for	O
the	O
Neo	B-Application
Geo	I-Application
MVS	I-Application
.	O
</s>
<s>
The	O
game	O
used	O
a	O
modified	O
version	O
of	O
the	O
engine	O
from	O
Metal	B-Application
Slug	I-Application
3	I-Application
,	O
which	O
eliminated	O
the	O
slowdown	O
problems	O
of	O
the	O
original	O
.	O
</s>
<s>
In	O
addition	O
to	O
increased	O
difficulty	O
,	O
Metal	B-Application
Slug	I-Application
X	O
introduced	O
several	O
changes	O
to	O
gameplay	O
and	O
presentation	O
:	O
</s>
<s>
Instead	O
of	O
individual	O
levels	O
being	O
set	O
at	O
either	O
day	O
or	O
night	O
,	O
the	O
stages	O
can	O
take	O
place	O
at	O
dusk	B-Application
,	O
twilight	O
,	O
or	O
sunset	B-Application
.	O
</s>
<s>
Several	O
new	O
weapons	O
are	O
included	O
:	O
Stones	O
,	O
Iron	O
Lizard	O
,	O
Enemy	O
Chaser	O
,	O
Super	O
Grenade	O
,	O
Drop	O
Shot	O
,	O
a	O
new	O
Golden	O
Metal	B-Application
Slug	I-Application
,	O
which	O
is	O
available	O
in	O
Mission	O
3	O
,	O
and	O
the	O
Armor	O
piercer	O
,	O
available	O
in	O
Mission	O
4	O
.	O
</s>
<s>
Added	O
Fio	O
's	O
death	O
sound	O
(	O
in	O
Metal	B-Application
Slug	I-Application
2	I-Application
,	O
she	O
uses	O
Eri	O
's	O
)	O
.	O
</s>
<s>
The	O
original	O
art	O
for	O
Metal	B-Application
Slug	I-Application
is	O
shown	O
at	O
the	O
end	O
of	O
the	O
game	O
while	O
the	O
credits	O
are	O
rolling	O
,	O
instead	O
of	O
the	O
black	O
screen	O
used	O
in	O
Metal	B-Application
Slug	I-Application
2	I-Application
.	O
</s>
<s>
Home	O
versions	O
of	O
Metal	B-Application
Slug	I-Application
2	I-Application
were	O
released	O
for	O
the	O
Neo	B-Application
Geo	I-Application
AES	I-Application
in	O
April	O
1998	B-Application
,	O
and	O
the	O
Neo	B-Device
Geo	I-Device
CD	I-Device
in	O
June	O
as	O
well	O
.	O
</s>
<s>
The	O
Neo	B-Device
Geo	I-Device
CD	I-Device
version	O
features	O
a	O
"	O
Combat	O
School	O
"	O
mode	O
(	O
similar	O
to	O
the	O
CD-ROM	O
based	O
versions	O
of	O
the	O
previous	O
game	O
)	O
where	O
the	O
player	O
can	O
play	O
new	O
versions	O
of	O
previously-played	O
missions	O
with	O
new	O
objectives	O
.	O
</s>
<s>
Metal	B-Application
Slug	I-Application
X	O
was	O
ported	O
to	O
the	O
Neo	B-Application
Geo	I-Application
AES	I-Application
in	O
May	O
1999	B-Application
and	O
the	O
PlayStation	B-Device
in	O
January	O
2001	B-Application
.	O
</s>
<s>
The	O
PlayStation	B-Device
version	O
was	O
released	O
in	O
North	O
America	O
and	O
PAL	O
regions	O
by	O
Agetec	O
and	O
features	O
the	O
same	O
"	O
Combat	O
School	O
"	O
mode	O
featured	O
in	O
the	O
Neo	B-Device
Geo	I-Device
CD	I-Device
versions	O
of	O
the	O
first	O
two	O
games	O
.	O
</s>
<s>
In	O
2006	O
,	O
Metal	B-Application
Slug	I-Application
Anthology	I-Application
(	O
titled	O
Metal	B-Application
Slug	I-Application
Complete	O
in	O
Japan	O
)	O
was	O
released	O
for	O
the	B-Operating_System
Wii	I-Operating_System
,	O
PlayStation	B-Device
2	I-Device
and	O
PSP	B-Operating_System
.	O
</s>
<s>
This	O
compilation	O
includes	O
the	O
original	O
Metal	B-Application
Slug	I-Application
,	O
and	O
all	O
of	O
its	O
arcade	O
sequels	O
(	O
including	O
Metal	B-Application
Slug	I-Application
2	I-Application
and	O
Metal	B-Application
Slug	I-Application
X	O
)	O
up	O
to	O
Metal	B-Application
Slug	I-Application
6	I-Application
.	O
</s>
<s>
The	O
AES	O
version	O
of	O
Metal	B-Application
Slug	I-Application
2	I-Application
was	O
released	O
in	O
October	O
2008	O
for	O
the	B-Operating_System
Wii	I-Operating_System
Virtual	B-Application
Console	I-Application
.	O
</s>
<s>
Both	O
Metal	B-Application
Slug	I-Application
2	I-Application
and	O
Metal	B-Application
Slug	I-Application
X	O
were	O
also	O
included	O
in	O
Metal	B-Application
Slug	I-Application
Collection	I-Application
PC	B-Device
,	O
which	O
was	O
released	O
in	O
Europe	O
in	O
2009	O
.	O
</s>
<s>
In	O
2013	O
,	O
versions	O
of	O
both	O
games	O
were	O
released	O
for	O
iOS	B-Application
and	O
Android	B-Application
.	O
</s>
<s>
The	O
original	O
arcade	O
version	O
of	O
Metal	B-Application
Slug	I-Application
X	O
became	O
available	O
on	O
Nintendo	B-Application
Switch	I-Application
via	O
ACA	B-Application
Neo	I-Application
Geo	I-Application
in	O
2017	O
.	O
</s>
<s>
Upon	O
their	O
initial	O
appearance	O
,	O
both	O
Metal	B-Application
Slug	I-Application
2	I-Application
and	O
Metal	B-Application
Slug	I-Application
X	O
received	O
generally	O
positive	O
reviews	O
.	O
</s>
<s>
For	O
example	O
,	O
the	O
iOS	B-Application
version	O
of	O
Metal	B-Application
Slug	I-Application
2	I-Application
holds	O
an	O
aggregate	O
score	O
of	O
77%	O
on	O
GameRankings	O
,	O
based	O
on	O
5	O
reviews	O
,	O
and	O
76	O
out	O
of	O
100	O
on	O
Metacritic	O
,	O
based	O
on	O
6	O
reviews	O
.	O
</s>
<s>
When	O
Metal	B-Application
Slug	I-Application
2	I-Application
was	O
released	O
on	O
the	O
Virtual	B-Application
Console	I-Application
in	O
2008	O
,	O
IGN	O
's	O
Lucas	O
M	O
.	O
Thomas	O
scored	O
it	O
7.5	O
out	O
of	O
10	O
.	O
</s>
<s>
He	O
was	O
highly	O
critical	O
of	O
the	O
slowdown	O
(	O
a	O
common	O
criticism	O
of	O
the	O
game	O
when	O
it	O
was	O
first	O
released	O
,	O
and	O
one	O
of	O
the	O
major	O
selling	O
points	O
for	O
Metal	B-Application
Slug	I-Application
X	O
)	O
,	O
but	O
praised	O
other	O
aspects	O
:	O
"	O
It	O
's	O
still	O
a	O
pretty	O
solid	O
game	O
on	O
its	O
own	O
,	O
and	O
there	O
's	O
no	O
denying	O
it	O
's	O
both	O
hilarious	O
and	O
filled	O
to	O
the	O
brim	O
with	O
great	O
run-and-gun	O
action	O
"	O
.	O
</s>
<s>
Eurogamer	O
's	O
Dan	O
Whitehead	O
scored	O
the	O
game	O
7	O
out	O
of	O
10	O
,	O
criticizing	O
the	O
price	O
:	O
"	O
The	O
Metal	B-Application
Slug	I-Application
Anthology	I-Application
collates	O
seven	O
games	O
from	O
the	O
series	O
on	O
disc	O
,	O
and	O
can	O
now	O
be	O
bought	O
for	O
just	O
over	O
twice	O
the	O
price	O
of	O
this	O
solitary	O
offering	O
.	O
</s>
<s>
If	O
you	O
like	O
frantic	O
blasting	O
and	O
silly	O
humour	O
then	O
I	O
heartily	O
recommend	O
you	O
seek	O
out	O
Metal	B-Application
Slug	I-Application
.	O
</s>
<s>
Just	O
do	O
n't	O
feel	O
obliged	O
to	O
do	O
it	O
via	O
Virtual	B-Application
Console	I-Application
"	O
.	O
</s>
<s>
Eurogamer	O
's	O
Tom	O
Bramwell	O
scored	O
the	O
2001	B-Application
PlayStation	B-Device
version	O
of	O
Metal	B-Application
Slug	I-Application
X	O
8	O
out	O
of	O
10	O
.	O
</s>
<s>
Although	O
he	O
felt	O
the	O
game	O
was	O
somewhat	O
dated	O
by	O
current	O
PlayStation	B-Device
standards	O
,	O
he	O
concluded	O
that	O
"	O
Metal	B-Application
Slug	I-Application
X	O
is	O
a	O
fan-pleasingly	O
simple	O
update	O
to	O
the	O
MS	O
series	O
,	O
and	O
to	O
the	O
rest	O
of	O
us	O
it	O
's	O
the	O
best	O
game	O
of	O
its	O
kind	O
on	O
the	O
PlayStation	B-Device
"	O
.	O
</s>
<s>
Game	O
Revolution	O
's	O
Johnny	O
Liu	O
rated	O
the	O
game	O
a	O
B	O
,	O
writing	O
"	O
as	O
there	O
are	O
fewer	O
and	O
fewer	O
good	O
Playstation	B-Device
games	O
,	O
let	O
alone	O
a	O
quality	O
port	O
.	O
</s>
<s>
GameSpot	O
's	O
Ryan	O
Davis	O
scored	O
it	O
8.2	O
out	O
of	O
10	O
,	O
writing	O
:	O
"	O
What	O
really	O
separates	O
Metal	B-Application
Slug	I-Application
X	O
from	O
the	O
rest	O
of	O
the	O
crowd	O
is	O
its	O
tongue-in-cheek	O
presentation	O
.	O
</s>
<s>
It	O
was	O
nominated	O
for	O
GameSpots	O
annual	O
"	O
Best	O
PlayStation	B-Device
Game	O
"	O
and	O
,	O
among	O
console	B-Application
games	I-Application
,	O
"	O
Best	O
Game	O
No	O
One	O
Played	O
"	O
prizes	O
.	O
</s>
<s>
Scott	O
Steinberg	O
reviewed	O
the	O
PlayStation	B-Device
version	O
of	O
Metal	B-Application
Slug	I-Application
X	O
for	O
Next	O
Generation	O
,	O
rating	O
it	O
three	O
stars	O
out	O
of	O
five	O
,	O
and	O
stated	O
that	O
"	O
a	O
derivative	O
but	O
instantly	O
endearing	O
military	O
shooter	O
that	O
earns	O
its	O
stripes	O
"	O
.	O
</s>
<s>
In	O
a	O
retrospective	O
review	O
,	O
Neo-Geo.com	O
scored	O
Metal	B-Application
Slug	I-Application
X	O
10	O
out	O
of	O
10	O
:	O
"	O
Metal	B-Application
Slug	I-Application
X	O
is	O
different	O
enough	O
in	O
many	O
small	O
ways	O
that	O
if	O
you	O
're	O
a	O
completist	O
,	O
you	O
'll	O
still	O
want	O
MS2	O
in	O
your	O
collection	O
.	O
</s>
<s>
However	O
,	O
if	O
you	O
're	O
simply	O
looking	O
for	O
the	O
best-playing	O
game	O
of	O
the	O
two	O
,	O
Metal	B-Application
Slug	I-Application
X	O
outshines	O
its	O
closely	O
related	O
cousin	O
with	O
a	O
simple	O
formula	O
of	O
"	O
more	O
,	O
more	O
,	O
and	O
more	O
"	O
.	O
</s>
<s>
In	O
Japan	O
,	O
Game	O
Machine	O
listed	O
Metal	B-Application
Slug	I-Application
2	I-Application
on	O
their	O
April	O
1	O
,	O
1998	B-Application
issue	O
as	O
being	O
the	O
third	O
most-successful	O
arcade	O
game	O
of	O
the	O
month	O
.	O
</s>
<s>
Game	O
Machine	O
also	O
listed	O
Metal	B-Application
Slug	I-Application
X	O
on	O
their	O
May	O
1	O
,	O
1999	B-Application
issue	O
as	O
being	O
the	O
seventh	O
most-successful	O
arcade	O
game	O
of	O
the	O
month	O
.	O
</s>
<s>
The	O
PlayStation	B-Device
port	O
of	O
Metal	B-Application
Slug	I-Application
X	O
sold	O
95,103	O
copies	O
in	O
Japan	O
,	O
and	O
69,035	O
copies	O
in	O
the	O
United	O
States	O
,	O
for	O
a	O
total	O
of	O
copies	O
sold	O
in	O
Japan	O
and	O
the	O
United	O
States	O
.	O
</s>
<s>
The	O
later	O
PC	B-Device
port	O
of	O
Metal	B-Application
Slug	I-Application
X	O
sold	O
229,374	O
digital	O
copies	O
worldwide	O
on	O
Steam	B-Application
,	O
for	O
a	O
total	O
of	O
at	O
least	O
Metal	B-Application
Slug	I-Application
X	O
copies	O
sold	O
for	O
the	O
PlayStation	B-Device
and	O
Steam	B-Application
platforms	O
.	O
</s>
