<s>
Action	B-Application
Half-Life	I-Application
is	O
a	O
mod	O
for	O
the	O
first-person	O
shooter	O
video	O
game	O
Half-Life	B-Application
.	O
</s>
<s>
Action	B-Application
Half-Life	I-Application
is	O
the	O
second	O
mod	O
in	O
the	O
"	O
Action	O
"	O
series	O
.	O
</s>
<s>
The	O
first	O
was	O
Action	B-Application
Quake	I-Application
2	I-Application
and	O
the	O
third	O
was	O
Action	O
Unreal	O
Tournament	O
2004	O
.	O
</s>
<s>
Unlike	O
the	O
buy	O
menu	O
in	O
Counter-Strike	B-Application
,	O
these	O
weapons	O
are	O
free	O
and	O
have	O
limited	O
ammunition	O
,	O
which	O
makes	O
tactical	O
usage	O
crucial	O
.	O
</s>
<s>
Action	B-Application
Half-life	I-Application
also	O
features	O
a	O
single	O
player	O
mode	O
.	O
</s>
<s>
Action	B-Application
Half-Life	I-Application
was	O
the	O
favored	O
modification	O
for	O
a	O
small	O
subculture	O
described	O
by	O
Rock	O
,	O
Paper	O
,	O
Shotgun	O
's	O
writer	O
Quintin	O
Smith	O
as	O
a	O
"	O
mad	O
cabal	O
of	O
mappers	O
who	O
obsessed	O
over	O
easter	O
eggs	O
"	O
,	O
with	O
some	O
levels	O
containing	O
secret	O
areas	O
much	O
larger	O
and	O
complex	O
than	O
the	O
main	O
level	O
.	O
</s>
