<s>
Pingus	B-Application
is	O
an	O
open-source	B-Application
video	I-Application
game	I-Application
programmed	O
by	O
German	O
developer	O
Ingo	O
Ruhnke	O
.	O
</s>
<s>
It	O
is	O
a	O
clone	O
of	O
Lemmings	B-Application
with	O
penguins	O
instead	O
of	O
lemmings	B-Application
.	O
</s>
<s>
Pingus	B-Application
has	O
55	O
levels	O
,	O
grouped	O
into	O
5	O
level	O
sets	O
,	O
as	O
well	O
as	O
21	O
winter-themed	O
tutorial	O
levels	O
.	O
</s>
<s>
Pingus	B-Application
0.7.2	O
introduced	O
'	O
levelsets	O
 '	O
,	O
which	O
are	O
lists	O
of	O
related	O
levels	O
;	O
levels	O
in	O
levelsets	O
usually	O
must	O
be	O
completed	O
in	O
order	O
.	O
</s>
<s>
Work	O
on	O
the	O
game	O
began	O
in	O
1998	B-Application
.	O
</s>
<s>
Version	O
0.6	O
was	O
released	O
in	O
2003	O
for	O
Linux	B-Application
,	O
and	O
featured	O
new	O
levels	O
and	O
a	O
level	O
editor	O
.	O
</s>
<s>
On	O
February	O
11	O
,	O
2006	O
the	O
game	O
began	O
being	O
ported	O
from	O
ClanLib	B-Language
to	O
Simple	B-Operating_System
DirectMedia	I-Operating_System
Layer	I-Operating_System
(	O
SDL	O
)	O
.	O
</s>
<s>
In	O
addition	O
to	O
Windows	B-Application
and	O
Linux	B-Application
,	O
the	O
switch	O
to	O
SDL	O
enabled	O
Pingus	B-Application
to	O
be	O
easily	O
built	O
on	O
other	O
platforms	O
,	O
including	O
Apple	O
's	O
OS	B-Operating_System
X	I-Operating_System
.	O
</s>
<s>
On	O
October	O
31	O
,	O
2007	O
,	O
version	O
0.7.2	O
was	O
released	O
with	O
a	O
set	O
of	O
Halloween-themed	O
levels	O
.	O
</s>
<s>
There	O
is	O
a	O
Windows	B-Application
0.7.6	O
and	O
an	O
Intel	O
OS	B-Operating_System
X	I-Operating_System
binary	O
of	O
0.7.2	O
available	O
from	O
the	O
Pingus	B-Application
website	O
.	O
</s>
<s>
There	O
is	O
a	O
PPC	B-Architecture
OS	B-Operating_System
X	I-Operating_System
binary	O
of	O
version	O
0.7.0	O
,	O
while	O
version	O
0.7.3	O
contains	O
minor	O
bug	O
fixes	O
that	O
allow	O
the	O
game	O
to	O
work	O
better	O
with	O
the	O
GNU	B-Application
Compiler	I-Application
Collection	I-Application
.	O
</s>
<s>
The	O
latest	O
version	O
,	O
0.7.6	O
,	O
adds	O
additional	O
Christmas	O
and	O
Halloween-themed	O
level	O
sets	O
.	O
</s>
<s>
In	O
July	O
2008	O
,	O
the	O
game	O
was	O
relicensed	O
from	O
the	O
GPL-2.0-or-later	B-License
to	O
the	O
GPL-3.0-or-later	B-License
.	O
</s>
<s>
This	O
game	O
was	O
the	O
first	O
"	O
Game	O
of	O
the	O
Month	O
"	O
by	O
The	O
Linux	B-Application
Game	O
Tome	O
.	O
</s>
<s>
Critics	O
were	O
favorable	O
toward	O
Pingus	B-Application
.	O
</s>
<s>
TechGage	O
named	O
Pingus	B-Application
among	O
the	O
"	O
Top	O
10	O
Free	O
Linux	B-Application
games	O
"	O
in	O
2006	O
.	O
</s>
<s>
CNN	B-Architecture
and	O
PC-Welt	O
ranked	O
it	O
as	O
one	O
of	O
the	O
best	O
free	B-Application
games	I-Application
available	O
for	O
Linux	B-Application
.	O
</s>
<s>
Thinkdigit	O
2009-05	O
ranked	O
Pingus	B-Application
among	O
the	O
"	O
Most	O
addictive	O
Linux	B-Application
games	O
"	O
.	O
</s>
<s>
Linux	B-Application
For	O
You	O
September	O
2009	O
ranked	O
Pingus	B-Application
5/5	O
.	O
</s>
<s>
About.com	O
called	O
it	O
a	O
great	O
game	O
,	O
while	O
acknowledging	O
its	O
debt	O
to	O
Lemmings	B-Application
.	O
</s>
