<s>
Crystal	B-Application
Defenders	I-Application
is	O
a	O
set	O
of	O
two	O
tower	B-Application
defense	I-Application
video	O
games	O
developed	O
and	O
published	O
by	O
Square	O
Enix	O
.	O
</s>
<s>
The	O
games	O
use	O
the	O
setting	O
of	O
Ivalice	O
and	O
design	O
elements	O
from	O
Final	B-Application
Fantasy	I-Application
Tactics	I-Application
A2	I-Application
:	I-Application
Grimoire	I-Application
of	I-Application
the	I-Application
Rift	I-Application
,	O
forming	O
part	O
of	O
the	O
wider	O
Final	B-Application
Fantasy	I-Application
franchise	O
.	O
</s>
<s>
The	O
games	O
feature	O
a	O
selection	O
of	O
characters	O
sporting	O
Final	O
Fantasy-based	O
character	O
classes	O
,	O
and	O
play	O
out	O
tower	B-Application
defense	I-Application
scenarios	O
against	O
recurring	O
series	O
of	O
monsters	O
.	O
</s>
<s>
The	O
first	O
game	O
in	O
the	O
series	O
is	O
Crystal	B-Application
Guardians	I-Application
,	O
which	O
was	O
released	O
in	O
three	O
parts	O
for	O
Japanese	O
mobile	O
phones	O
in	O
2008	O
.	O
</s>
<s>
It	O
was	O
adapted	O
for	O
iOS	B-Application
later	O
that	O
year	O
as	O
Square	O
Enix	O
's	O
first	O
game	O
for	O
the	O
platform	O
,	O
and	O
renamed	O
Crystal	B-Application
Defenders	I-Application
.	O
</s>
<s>
Under	O
that	O
name	O
,	O
the	O
game	O
was	O
also	O
released	O
between	O
2009	O
and	O
2011	O
for	O
Android	B-Application
,	O
Xbox	B-Device
Live	I-Device
Arcade	I-Device
,	O
WiiWare	O
,	O
and	O
PlayStation	B-Operating_System
3	I-Operating_System
and	O
PlayStation	B-Operating_System
Portable	I-Operating_System
via	O
the	O
PlayStation	O
Store	O
.	O
</s>
<s>
It	O
was	O
re-released	O
with	O
graphical	O
improvements	O
for	O
iOS	B-Application
as	O
Crystal	B-Application
Defenders	I-Application
Plus	I-Application
in	O
2013	O
.	O
</s>
<s>
A	O
sequel	O
,	O
Crystal	B-Application
Defenders	I-Application
:	I-Application
Vanguard	I-Application
Storm	I-Application
,	O
was	O
released	O
for	O
iOS	B-Application
in	O
2009	O
.	O
</s>
<s>
Vanguard	B-Application
Storm	I-Application
,	O
in	O
contrast	O
,	O
has	O
the	O
player	O
place	O
troops	O
on	O
the	O
right	O
half	O
of	O
a	O
grid	O
that	O
enemies	O
move	O
across	O
in	O
one	O
square	O
per	O
turn	O
,	O
with	O
the	O
player	O
adjusting	O
the	O
placement	O
of	O
their	O
forces	O
every	O
turn	O
.	O
</s>
<s>
Crystal	B-Application
Defenders	I-Application
was	O
Square	O
Enix	O
's	O
first	O
game	O
for	O
smartphones	B-Application
,	O
while	O
Vanguard	B-Application
Storm	I-Application
was	O
its	O
first	O
game	O
to	O
be	O
designed	O
especially	O
for	O
touchscreen	O
controls	O
.	O
</s>
<s>
The	O
games	O
use	O
character	O
designs	O
and	O
music	O
created	O
for	O
Tactics	B-Application
A2	I-Application
by	O
artist	O
Ryoma	O
Itō	O
and	O
composer	O
Hitoshi	O
Sakimoto	O
,	O
and	O
the	O
series	O
was	O
produced	O
by	O
Takehiro	O
Ando	O
.	O
</s>
<s>
Vanguard	B-Application
Storm	I-Application
received	O
more	O
praise	O
from	O
critics	O
,	O
who	O
appreciated	O
the	O
graphics	O
and	O
found	O
the	O
gameplay	O
fun	O
,	O
though	O
not	O
without	O
flaws	O
.	O
</s>
<s>
All	O
of	O
the	O
releases	O
in	O
the	O
Crystal	B-Application
Defenders	I-Application
series	O
are	O
tower	B-Application
defense	I-Application
games	I-Application
composed	O
of	O
multiple	O
stages	O
,	O
each	O
consisting	O
of	O
a	O
top-down	O
view	O
of	O
a	O
winding	O
path	O
.	O
</s>
<s>
The	O
first	O
game	O
,	O
originally	O
named	O
Crystal	B-Application
Guardians	I-Application
and	O
later	O
renamed	O
Crystal	B-Application
Defenders	I-Application
,	O
was	O
released	O
in	O
three	O
separate	O
chapters	O
named	O
W1	O
,	O
W2	O
,	O
and	O
W3	O
.	O
</s>
<s>
The	B-Operating_System
Wii	I-Operating_System
version	O
of	O
Crystal	B-Application
Defenders	I-Application
is	O
divided	O
into	O
R1	O
and	O
R2	O
chapters	O
and	O
offers	O
a	O
new	O
ranking	O
system	O
via	O
Nintendo	B-Application
Wi-Fi	I-Application
Connection	I-Application
.	O
</s>
<s>
In	O
Crystal	B-Application
Defenders	I-Application
:	I-Application
Vanguard	I-Application
Storm	I-Application
the	O
maps	O
no	O
longer	O
have	O
winding	O
pathways	O
,	O
but	O
instead	O
are	O
four	O
rows	O
of	O
eight	O
squares	O
.	O
</s>
<s>
Three	O
developers	O
have	O
worked	O
on	O
the	O
Crystal	B-Application
Defenders	I-Application
series	O
;	O
the	O
series	O
as	O
a	O
whole	O
was	O
supervised	O
by	O
Final	B-Application
Fantasy	I-Application
franchise	O
owner	O
Square	O
Enix	O
.	O
</s>
<s>
External	O
studios	O
Mobile	O
Software	O
Foundation	O
and	O
Winds	O
worked	O
with	O
Square	O
Enix	O
on	O
Crystal	B-Application
Guardians	I-Application
and	O
Crystal	B-Application
Defenders	I-Application
,	O
while	O
Square	O
Enix	O
worked	O
alone	O
on	O
Crystal	B-Application
Defenders	I-Application
:	I-Application
Vanguard	I-Application
Storm	I-Application
.	O
</s>
<s>
The	O
Crystal	B-Application
Defenders	I-Application
series	O
uses	O
the	O
recurring	O
setting	O
of	O
Ivalice	O
,	O
specifically	O
recycling	O
character	O
designs	O
and	O
aesthetic	O
elements	O
from	O
the	O
Nintendo	B-Device
DS	I-Device
title	O
Final	B-Application
Fantasy	I-Application
Tactics	I-Application
A2	I-Application
:	I-Application
Grimoire	I-Application
of	I-Application
the	I-Application
Rift	I-Application
.	O
</s>
<s>
The	O
series	O
reuses	O
music	O
from	O
Tactics	B-Application
A2	I-Application
composed	O
by	O
Hitoshi	O
Sakimoto	O
and	O
other	O
composers	O
from	O
Sakimoto	O
's	O
studio	O
Basiscape	O
.	O
</s>
<s>
The	O
character	O
designs	O
were	O
created	O
by	O
Ryoma	O
Itō	O
,	O
who	O
had	O
previously	O
worked	O
on	O
Final	B-Application
Fantasy	I-Application
Tactics	I-Application
Advance	I-Application
,	O
Tactics	B-Application
A2	I-Application
and	O
Final	B-Application
Fantasy	I-Application
XII	I-Application
:	I-Application
Revenant	I-Application
Wings	I-Application
.	O
</s>
<s>
Crystal	B-Application
Defenders	I-Application
was	O
Square	O
Enix	O
's	O
first	O
game	O
for	O
smartphones	B-Application
.	O
</s>
<s>
Vanguard	B-Application
Storm	I-Application
was	O
the	O
first	O
Square	O
Enix	O
game	O
to	O
be	O
designed	O
especially	O
for	O
touchscreen	O
controls	O
.	O
</s>
<s>
Crystal	B-Application
Guardians	I-Application
was	O
released	O
in	O
three	O
separate	O
chapters	O
for	O
mobile	O
phones	O
in	O
Japan	O
in	O
2008	O
.	O
</s>
<s>
It	O
was	O
released	O
on	O
January	O
1	O
,	O
March	O
10	O
,	O
and	O
May	O
5	O
for	O
i-mode	O
,	O
April	O
1	O
,	O
June	O
2	O
,	O
and	O
July	O
16	O
for	O
Yahoo	B-Application
!	I-Application
</s>
<s>
The	O
game	O
was	O
released	O
worldwide	O
on	O
December	O
23	O
the	O
same	O
year	O
as	O
Crystal	B-Application
Defenders	I-Application
for	O
iOS	B-Application
devices	O
and	O
iPods	B-Device
,	O
with	O
all	O
three	O
chapters	O
releasing	O
simultaneously	O
.	O
</s>
<s>
This	O
version	O
was	O
ported	O
to	O
Xbox	B-Device
Live	I-Device
Arcade	I-Device
worldwide	O
for	O
the	B-Operating_System
Xbox	I-Operating_System
360	I-Operating_System
and	O
via	O
the	O
PlayStation	O
Store	O
for	O
PlayStation	B-Operating_System
3	I-Operating_System
in	O
Japan	O
on	O
March	O
11	O
,	O
2009	O
.	O
</s>
<s>
The	O
PlayStation	B-Operating_System
3	I-Operating_System
version	O
was	O
released	O
outside	O
of	O
Japan	O
on	O
August	O
6	O
.	O
</s>
<s>
The	O
game	O
was	O
also	O
ported	O
via	O
the	O
PlayStation	O
Store	O
for	O
PlayStation	B-Operating_System
Portable	I-Operating_System
on	O
October	O
29	O
,	O
2009	O
and	O
optimized	O
for	O
the	O
iPad	B-Device
on	O
July	O
1	O
,	O
2010	O
.	O
</s>
<s>
The	O
game	O
was	O
released	O
on	O
Android	B-Application
on	O
January	O
25	O
,	O
2011	O
,	O
though	O
only	O
the	O
W1	O
and	O
W2	O
chapters	O
were	O
released	O
.	O
</s>
<s>
The	O
game	O
was	O
re-released	O
for	O
iOS	B-Application
with	O
higher	O
quality	O
graphics	O
as	O
Crystal	B-Application
Defenders	I-Application
Plus	I-Application
on	O
February	O
20	O
,	O
2013	O
;	O
W1	O
was	O
made	O
free	O
with	O
the	O
other	O
chapters	O
available	O
as	O
in-app	O
purchases	O
.	O
</s>
<s>
Distribution	O
of	O
Crystal	B-Application
Defenders	I-Application
Plus	I-Application
and	O
Crystal	O
Defenderss	O
iOS	B-Application
version	O
ended	O
in	O
May	O
2016	O
.	O
</s>
<s>
Crystal	B-Application
Defenders	I-Application
:	I-Application
Vanguard	I-Application
Storm	I-Application
was	O
released	O
worldwide	O
for	O
iOS	B-Application
on	O
May	O
13	O
,	O
2009	O
.	O
</s>
<s>
Distribution	O
of	O
Vanguard	B-Application
Storm	I-Application
ended	O
in	O
August	O
2017	O
.	O
</s>
<s>
The	O
series	O
,	O
especially	O
Crystal	B-Application
Defenders	I-Application
,	O
has	O
sold	O
well	O
,	O
with	O
Defenders	O
achieving	O
one	O
million	O
downloads	O
worldwide	O
as	O
of	O
December	O
2012	O
.	O
</s>
<s>
Overall	O
critical	O
response	O
to	O
the	O
series	O
has	O
been	O
mixed	O
,	O
however	O
,	O
with	O
Defenders	O
receiving	O
poor	O
reviews	O
and	O
Vanguard	B-Application
Storm	I-Application
earning	O
a	O
more	O
mixed	O
reception	O
.	O
</s>
<s>
Reaction	O
to	O
the	O
presentation	O
of	O
the	O
mobile	O
versions	O
of	O
Crystal	B-Application
Defenders	I-Application
and	O
its	O
ports	O
were	O
mixed	O
;	O
Connor	O
Egan	O
of	O
Slide	O
to	O
Play	O
noted	O
that	O
it	O
"	O
faithfully	O
reproduces	O
the	O
look	O
of	O
the	O
Final	B-Application
Fantasy	I-Application
Tactics	O
series	O
"	O
,	O
but	O
found	O
that	O
the	O
control	O
scheme	O
made	O
the	O
gameplay	O
area	O
feel	O
small	O
and	O
cramped	O
.	O
</s>
<s>
Sam	O
Bishop	O
of	O
IGN	O
criticized	O
the	O
visuals	O
of	O
the	O
PlayStation	B-Operating_System
3	I-Operating_System
port	O
of	O
the	O
game	O
for	O
being	O
"	O
minimally	O
animated	O
"	O
phone	O
graphics	O
with	O
a	O
border	O
around	O
them	O
,	O
though	O
he	O
praised	O
the	O
music	O
.	O
</s>
<s>
IGNs	O
Ryan	O
Geddes	O
,	O
in	O
reviewing	O
the	B-Operating_System
Xbox	I-Operating_System
360	I-Operating_System
version	O
,	O
was	O
much	O
harsher	O
:	O
he	O
dismissed	O
the	O
character	O
designs	O
as	O
"	O
generic	O
looking	O
"	O
and	O
the	O
animation	O
quality	O
as	O
"	O
dull	O
"	O
,	O
though	O
he	O
had	O
no	O
complaints	O
about	O
the	O
music	O
or	O
sound	O
effects	O
.	O
</s>
<s>
Tom	O
McShea	O
of	O
GameSpot	O
had	O
similar	O
complaints	O
about	O
the	B-Operating_System
Xbox	I-Operating_System
360	I-Operating_System
version	O
,	O
calling	O
the	O
character	O
graphics	O
"	O
devoid	O
of	O
personality	O
"	O
with	O
minimal	O
animation	O
.	O
</s>
<s>
Both	O
Egan	O
and	O
Bishop	O
were	O
more	O
positive	O
to	O
the	O
game	O
,	O
feeling	O
that	O
it	O
was	O
a	O
competent	O
example	O
of	O
a	O
tower	B-Application
defense	I-Application
game	I-Application
,	O
but	O
Egan	O
felt	O
that	O
the	O
"	O
ungainly	O
and	O
amateurish	O
controls	O
damage	O
the	O
experience	O
"	O
,	O
and	O
both	O
reviewers	O
found	O
the	O
game	O
to	O
be	O
very	O
difficult	O
to	O
complete	O
.	O
</s>
<s>
Crystal	B-Application
Defenders	I-Application
:	I-Application
Vanguard	I-Application
Storm	I-Application
received	O
more	O
favorable	O
reviews	O
than	O
the	O
original	O
game	O
.	O
</s>
<s>
Reactions	O
were	O
more	O
mixed	O
to	O
the	O
gameplay	O
,	O
however	O
:	O
Buchannan	O
praised	O
the	O
"	O
fun	O
"	O
gameplay	O
and	O
deemed	O
it	O
superior	O
to	O
the	O
original	O
game	O
,	O
Tracy	O
Erikson	O
of	O
Pocket	O
Gamer	O
praised	O
the	O
"	O
solid	O
gameplay	O
and	O
fine	O
balancing	O
"	O
,	O
and	O
Nick	O
Gillett	O
of	O
The	O
Guardian	O
called	O
it	O
"	O
simple	O
,	O
clever	O
and	O
compelling	O
"	O
with	O
a	O
higher	O
level	O
of	O
polish	O
and	O
quality	O
than	O
other	O
mobile	O
tower	B-Application
defense	I-Application
games	I-Application
.	O
</s>
<s>
The	O
Touch	O
Arcade	O
review	O
,	O
in	O
contrast	O
,	O
felt	O
instead	O
that	O
it	O
was	O
a	O
solid	O
casual	O
game	O
with	O
flaws	O
,	O
while	O
Kamblad	O
derided	O
it	O
as	O
"	O
a	O
strategy	O
game	O
where	O
strategy	O
is	O
n't	O
important	O
"	O
and	O
the	O
Slide	O
to	O
Play	O
review	O
said	O
that	O
it	O
had	O
a	O
solid	O
base	O
that	O
the	O
game	O
failed	O
to	O
make	O
the	O
most	O
of	O
,	O
with	O
too	O
many	O
holes	O
in	O
the	O
gameplay	O
to	O
recommend	O
to	O
players	O
who	O
were	O
not	O
Final	B-Application
Fantasy	I-Application
fans	O
.	O
</s>
