<s>
is	O
a	O
vertical	O
scrolling	O
shooter	O
video	O
game	O
developed	O
and	O
published	O
by	O
T&E	O
Soft	O
for	O
the	O
Nintendo	B-Device
Game	I-Device
Boy	I-Device
exclusively	O
in	O
Japan	O
on	O
December	O
18	O
,	O
1992	O
.	O
</s>
<s>
Sometime	O
in	O
the	O
21st	O
century	O
,	O
humanity	O
leaves	O
Earth	O
for	O
Mars	B-Application
due	O
to	O
a	O
legacy	O
of	O
environmental	O
pollution	O
on	O
their	O
home	O
planet	O
.	O
</s>
<s>
The	O
gameplay	O
is	O
done	O
in	O
a	O
style	O
similar	O
to	O
Gradius	B-Application
and	O
R-Type	B-Application
.	O
</s>
<s>
As	O
a	O
complex	O
scrolling	O
shooter	O
,	O
this	O
game	O
attempts	O
to	O
emulate	O
multiple	O
dimensions	O
using	O
the	O
limitations	O
of	O
the	O
Game	B-Device
Boy	I-Device
console	O
.	O
</s>
<s>
The	O
parallax	B-Device
backgrounds	O
and	O
elaborate	O
detailing	O
in	O
the	O
sprites	O
help	O
to	O
create	O
a	O
unique	O
Game	B-Device
Boy	I-Device
experience	O
;	O
any	O
distinctions	O
between	O
the	O
scenery	O
and	O
the	O
bad	O
guys	O
are	O
clearly	O
shown	O
through	O
different	O
shades	O
of	O
the	O
same	O
color	O
.	O
</s>
<s>
A	O
higher	O
degree	O
of	O
difficulty	O
exists	O
in	O
this	O
game	O
as	O
opposed	O
to	O
most	O
Game	B-Device
Boy	I-Device
scrolling	O
shooters	O
of	O
that	O
era	O
.	O
</s>
<s>
Video	O
gaming	O
website	O
Blame	O
the	O
Control	O
Pad	O
praises	O
Chikyū	B-Application
Kaihō	I-Application
Gun	I-Application
ZAS	I-Application
for	O
its	O
innovative	O
gameplay	O
along	O
with	O
its	O
integrated	O
levels	O
and	O
player-friendly	O
control	O
scheme	O
.	O
</s>
