<s>
A	O
port	O
for	O
the	B-Operating_System
Dreamcast	I-Operating_System
was	O
released	O
in	O
2006	O
and	O
marketed	O
as	O
the	O
last	O
game	O
for	O
the	O
system	O
,	O
although	O
two	O
more	O
were	O
released	O
the	O
following	O
year	O
.	O
</s>
<s>
A	O
high-definition	O
remaster	O
,	O
Under	B-Application
Defeat	I-Application
HD	O
,	O
was	O
released	O
for	O
the	O
PlayStation	B-Operating_System
3	I-Operating_System
and	O
Xbox	B-Operating_System
360	I-Operating_System
in	O
2012	O
,	O
published	O
by	O
Rising	O
Star	O
Games	O
.	O
</s>
<s>
This	O
version	O
was	O
re-released	O
in	O
arcades	O
as	O
Under	B-Application
Defeat	I-Application
HD+	O
.	O
</s>
<s>
In	O
Under	B-Application
Defeat	I-Application
,	O
the	O
player	O
assumes	O
control	O
of	O
a	O
helicopter	O
.	O
</s>
<s>
The	O
gameplay	O
bears	O
resemblance	O
to	O
early	O
Toaplan	O
games	O
such	O
as	O
Twin	B-Application
Cobra	I-Application
.	O
</s>
<s>
Under	B-Application
Defeat	I-Application
was	O
developed	O
by	O
G.rev	O
for	O
Sega	O
's	O
NAOMI	O
arcade	O
board	O
.	O
</s>
<s>
A	O
Dreamcast	B-Operating_System
port	O
was	O
released	O
on	O
March	O
23	O
,	O
2006	O
,	O
over	O
five	O
years	O
after	O
Sega	O
announced	O
they	O
were	O
pulling	O
support	O
for	O
the	O
system	O
.	O
</s>
<s>
G.rev	O
promoted	O
it	O
as	O
the	O
last	O
Dreamcast	B-Operating_System
game	O
,	O
although	O
Triggerheart	O
Exelica	O
and	O
Karous	B-Application
were	O
released	O
for	O
the	O
system	O
the	O
following	O
year	O
.	O
</s>
<s>
It	O
sold	O
through	O
its	O
first	O
printing	O
within	O
one	O
week	O
,	O
becoming	O
the	O
best-selling	O
game	O
on	O
the	O
system	O
since	O
G.rev	O
'	O
s	O
own	O
Border	B-Application
Down	I-Application
(	O
2003	O
)	O
.	O
</s>
<s>
Dreamcast	B-Operating_System
copies	O
were	O
released	O
in	O
limited	O
numbers	O
and	O
continue	O
to	O
command	O
high	O
prices	O
on	O
secondary	O
markets	O
.	O
</s>
<s>
In	O
response	O
to	O
fan	O
requests	O
for	O
a	O
re-release	O
,	O
G.rev	O
announced	O
a	O
high-definition	O
version	O
of	O
Under	B-Application
Defeat	I-Application
for	O
PlayStation	B-Operating_System
3	I-Operating_System
and	O
Xbox	B-Operating_System
360	I-Operating_System
in	O
October	O
2011	O
.	O
</s>
<s>
The	O
re-release	O
was	O
titled	O
Under	B-Application
Defeat	I-Application
HD	O
published	O
by	O
Rising	O
Star	O
Games	O
.	O
</s>
<s>
Most	O
of	O
G.rev	O
'	O
s	O
recent	O
games	O
were	O
Xbox	B-Operating_System
360	I-Operating_System
exclusives	O
,	O
so	O
out	O
of	O
fear	O
of	O
being	O
framed	O
exclusively	O
as	O
Xbox	B-Operating_System
360	I-Operating_System
developers	O
in	O
the	O
industry	O
,	O
they	O
decided	O
to	O
create	O
a	O
PlayStation	B-Operating_System
3	I-Operating_System
port	O
as	O
well	O
.	O
</s>
<s>
An	O
arcade	O
version	O
was	O
released	O
in	O
2013	O
as	O
Under	B-Application
Defeat	I-Application
HD+	O
.	O
</s>
<s>
Building	O
on	O
the	O
original	O
,	O
Under	B-Application
Defeat	I-Application
HD	O
has	O
a	O
new	O
gameplay	O
mode	O
,	O
New	O
Order	O
mode	O
,	O
which	O
stretches	O
the	O
gameplay	O
to	O
fill	O
a	O
16:9	O
display	O
and	O
gives	O
the	O
player	O
the	O
ability	O
to	O
shoot	O
at	O
wider	O
ranges	O
.	O
</s>
<s>
Under	B-Application
Defeat	I-Application
HD	O
also	O
has	O
improved	O
shadowing	O
and	O
textures	O
.	O
</s>
<s>
The	O
team	O
also	O
needed	O
to	O
manually	O
reproduce	O
the	O
deferred	O
background	O
polygon	O
rendering	O
,	O
a	O
process	O
handled	O
by	O
PowerVR	B-Device
technology	O
in	O
the	O
original	O
arcade	O
and	O
Dreamcast	B-Operating_System
hardware	O
.	O
</s>
<s>
Reviewing	O
the	B-Operating_System
Dreamcast	I-Operating_System
version	O
,	O
Edge	O
and	O
Eurogamer	O
agreed	O
that	O
Under	B-Application
Defeat	I-Application
was	O
traditional	O
in	O
its	O
gameplay	O
,	O
absent	O
of	O
the	O
more	O
inventive	O
bullet	O
patterns	O
,	O
scoring	O
methods	O
,	O
and	O
controls	O
seen	O
in	O
modern	O
shooters	O
.	O
</s>
<s>
They	O
also	O
argued	O
that	O
the	O
scarcity	O
of	O
good	O
shoot	O
'	O
em	O
ups	O
may	O
influence	O
fans	O
of	O
the	O
genre	O
to	O
overstate	O
Under	B-Application
Defeat	I-Application
's	O
quality	O
.	O
</s>
<s>
In	O
a	O
retrospective	O
review	O
,	O
Retro	O
Gamer	O
praised	O
the	O
game	O
's	O
particle	O
effects	O
and	O
wrote	O
that	O
Under	B-Application
Defeat	I-Application
"	O
shows	O
how	O
,	O
with	O
good	O
developers	O
,	O
the	B-Operating_System
Dreamcast	I-Operating_System
was	O
perfectly	O
capable	O
of	O
hanging	O
with	O
the	O
competition.	O
"	O
</s>
<s>
Destructoid	O
wrote	O
that	O
"	O
getting	O
used	O
to	O
Under	B-Application
Defeat	I-Application
’s	O
controls	O
is	O
both	O
the	O
game	O
's	O
blessing	O
and	O
curse	O
"	O
,	O
believing	O
that	O
perhaps	O
the	O
game	O
was	O
developed	O
for	O
arcade	O
sticks	O
and	O
a	O
standard	O
controller	O
was	O
not	O
ideal	O
.	O
</s>
