<s>
Sanctum	B-Application
is	O
a	O
first-person	O
shooter	O
tower	B-Application
defense	I-Application
video	O
game	O
,	O
developed	O
by	O
independent	O
developer	O
Coffee	O
Stain	O
Studios	O
.	O
</s>
<s>
It	O
was	O
released	O
on	O
Steam	B-Application
for	O
Microsoft	B-Application
Windows	I-Application
on	O
15	O
April	O
2011	O
.	O
</s>
<s>
The	O
successor	O
,	O
Sanctum	B-Application
2	I-Application
,	O
was	O
announced	O
in	O
2012	O
and	O
released	O
in	O
May	O
2013	O
.	O
</s>
<s>
In	O
Sanctum	B-Application
,	O
players	O
take	O
on	O
the	O
role	O
of	O
Skye	O
,	O
an	O
elite	O
soldier	O
sent	O
out	O
to	O
protect	O
her	O
home	O
town	O
,	O
Elysion	O
One	O
,	O
from	O
hordes	O
of	O
mysterious	O
alien	O
creatures	O
.	O
</s>
<s>
The	O
gameplay	O
in	O
Sanctum	B-Application
is	O
divided	O
into	O
the	O
building	O
phase	O
and	O
the	O
extermination	O
phase	O
.	O
</s>
<s>
Unlike	O
most	O
tower	B-Application
defense	I-Application
games	I-Application
,	O
the	O
player	O
is	O
allowed	O
to	O
move	O
about	O
the	O
level	O
during	O
this	O
phase	O
and	O
attack	O
enemies	O
with	O
different	O
weapon	O
types	O
,	O
much	O
like	O
in	O
a	O
typical	O
first-person	O
shooter	O
.	O
</s>
<s>
The	O
beta	O
was	O
made	O
available	O
to	O
all	O
people	O
who	O
pre-purchased	O
the	O
game	O
on	O
Steam	B-Application
.	O
</s>
<s>
Sanctum	B-Application
received	O
mixed	O
reviews	O
from	O
critics	O
.	O
</s>
<s>
Sanctum	B-Application
sold	O
more	O
than	O
180.000	O
copies	O
via	O
digital	O
distribution	O
by	O
August	O
2011	O
.	O
</s>
