<s>
Code	B-Application
Name	I-Application
:	I-Application
Viper	I-Application
,	O
known	O
in	O
Japan	O
as	O
,	O
is	O
an	O
action-platform	O
video	O
game	O
developed	O
by	O
Arc	O
System	O
Works	O
and	O
published	O
by	O
Capcom	O
in	O
1990	O
for	O
the	O
Nintendo	O
Entertainment	O
System	O
.	O
</s>
<s>
The	O
gameplay	O
system	O
is	O
similar	O
to	O
Namco	O
's	O
1986	O
arcade	O
game	O
Rolling	B-Application
Thunder	I-Application
,	O
specifically	O
its	O
own	O
NES	O
version	O
.	O
</s>
<s>
Like	O
in	O
Rolling	B-Application
Thunder	I-Application
,	O
the	O
player	O
can	O
jump	O
or	O
drop	O
down	O
between	O
floors	O
by	O
holding	O
the	O
directional	O
pad	O
up	O
or	O
down	O
and	O
pressing	O
the	O
jump	O
button	O
,	O
as	O
well	O
as	O
enter	O
doors	O
to	O
obtain	O
power-ups	O
or	O
avoid	O
enemies	O
.	O
</s>
<s>
Unlike	O
Rolling	B-Application
Thunder	I-Application
,	O
the	O
player	O
can	O
shoot	O
while	O
jumping	O
and	O
can	O
also	O
change	O
directions	O
during	O
midair	O
.	O
</s>
<s>
Another	O
difference	O
between	O
Rolling	B-Application
Thunder	I-Application
and	O
Code	B-Application
Name	I-Application
:	I-Application
Viper	I-Application
is	O
the	O
added	O
emphasis	O
on	O
rescuing	O
hostages	O
,	O
like	O
the	O
also-similar	O
Shinobi	B-Application
.	O
</s>
<s>
Per	O
Rolling	B-Application
Thunder	I-Application
,	O
the	O
strength	O
and	O
attack	O
patterns	O
of	O
the	O
standard	O
enemy	O
soldiers	O
that	O
the	O
player	O
will	O
face	O
is	O
determined	O
by	O
the	O
colors	O
of	O
their	O
outfit	O
,	O
and	O
"	O
strange	O
"	O
enemies	O
,	O
such	O
as	O
Snipers	O
,	O
Frogmen	O
,	O
and	O
Maniacs	O
,	O
appear	O
later	O
on	O
.	O
</s>
