<s>
Crossfire	B-Protocol
is	O
a	O
free	B-Application
and	I-Application
open	I-Application
source	I-Application
software	I-Application
cross-platform	B-Operating_System
multiplayer	O
online	O
role-playing	O
video	O
game	O
.	O
</s>
<s>
All	O
content	O
is	O
licensed	O
under	O
the	O
GNU	B-License
GPL-2.0-or-later	I-License
.	O
</s>
<s>
The	O
client	O
and	O
server	O
will	O
run	O
in	O
Microsoft	B-Application
Windows	I-Application
,	O
Mac	B-Application
OS	I-Application
X	I-Application
,	O
Linux	B-Application
,	O
IRIX	B-Operating_System
,	O
and	O
an	O
array	O
of	O
other	O
platforms	O
.	O
</s>
<s>
is	O
a	O
multi-player	O
online	O
role-playing	O
game	O
;	O
it	O
can	O
be	O
described	O
as	O
a	O
cross-over	O
of	O
the	O
ideas	O
of	O
Nethack	B-Application
,	O
Ultima	O
and	O
Gauntlet	B-Device
.	O
</s>
<s>
It	O
originally	O
started	O
as	O
a	O
Gauntlet	B-Device
clone	O
developed	O
by	O
Frank	O
Tore	O
Johansen	O
at	O
the	O
University	O
of	O
Oslo	O
in	O
Norway	O
.	O
</s>
<s>
After	O
a	O
name	O
change	O
in	O
that	O
same	O
year	O
and	O
brief	O
hosting	O
time	O
at	O
University	O
of	O
California	O
,	O
Berkeley	O
(	O
Jul-1999	O
to	O
Jan-2001	O
)	O
,	O
the	O
project	O
now	O
resides	O
at	O
SourceForge	B-Application
where	O
development	O
continues	O
.	O
</s>
<s>
Although	O
there	O
are	O
many	O
quests	O
,	O
the	O
game	O
leans	O
towards	O
hack	B-Application
and	I-Application
slash	I-Application
adventuring	O
with	O
other	O
players	O
.	O
</s>
<s>
was	O
used	O
as	O
the	O
base	O
of	O
a	O
number	O
of	O
commercial	O
and	O
free	O
MMORPGs	B-Protocol
,	O
such	O
as	O
,	O
a	O
Java	B-Language
rewrite	O
,	O
,	O
which	O
closed	O
its	O
code	O
and	O
content	O
,	O
and	O
,	O
which	O
only	O
used	O
the	O
server	O
code	O
but	O
features	O
an	O
isometric	O
view	O
and	O
a	O
different	O
project	O
philosophy	O
focused	O
on	O
a	O
single	O
main	O
server	O
.	O
</s>
<s>
is	O
another	O
fork	B-Application
of	O
the	O
Crossfire	B-Protocol
project	O
,	O
primarily	O
aiming	O
to	O
improve	O
the	O
quality	O
of	O
its	O
code	O
and	O
in-game	O
content	O
.	O
</s>
<s>
In	O
1999	O
was	O
featured	O
by	O
Linux	B-Application
Journal	O
.	O
</s>
<s>
The	O
game	O
was	O
downloaded	O
over	O
550,000	O
times	O
from	O
SourceForge.net	B-Application
between	O
2000	O
and	O
April	O
2020	O
.	O
</s>
