<s>
Subnautica	B-Application
:	I-Application
Below	I-Application
Zero	I-Application
is	O
an	O
open-world	O
survival	B-Application
action-adventure	O
video	O
game	O
developed	O
and	O
published	O
by	O
Unknown	O
Worlds	O
Entertainment	O
.	O
</s>
<s>
It	O
is	O
the	O
sequel	O
to	O
the	O
2018	O
game	O
Subnautica	B-Application
.	O
</s>
<s>
Introduced	O
in	O
early	O
access	O
via	O
Steam	B-Application
and	O
the	O
Epic	O
Games	O
Store	O
in	O
January	O
2019	O
,	O
Subnautica	B-Application
:	I-Application
Below	I-Application
Zero	I-Application
was	O
released	O
for	O
the	O
macOS	B-Application
,	O
Nintendo	B-Application
Switch	I-Application
,	O
PlayStation	B-Operating_System
4	I-Operating_System
,	O
PlayStation	B-Device
5	I-Device
,	O
Windows	O
,	O
Xbox	B-Device
One	I-Device
,	O
and	O
Xbox	B-Device
Series	I-Device
X/S	I-Device
on	O
May	O
14	O
,	O
2021	O
.	O
</s>
<s>
Subnautica	B-Application
:	I-Application
Below	I-Application
Zero	I-Application
is	O
a	O
survival	B-Application
adventure	O
game	O
set	O
in	O
an	O
open	O
world	O
environment	O
and	O
played	O
from	O
a	O
first-person	O
perspective	O
.	O
</s>
<s>
Survival	B-Application
—	O
The	O
player	O
must	O
manage	O
health	O
,	O
hunger	O
,	O
thirst	O
,	O
oxygen	O
and	O
temperature	O
.	O
</s>
<s>
Freedom	O
Mode	O
—	O
Just	O
like	O
survival	B-Application
,	O
but	O
with	O
hunger	O
and	O
thirst	O
disabled	O
.	O
</s>
<s>
Hardcore	B-Application
Mode	I-Application
—	O
Survival	B-Application
mode	O
with	O
permadeath	B-Application
.	O
</s>
<s>
Two	O
years	O
after	O
the	O
events	O
of	O
the	B-Application
original	I-Application
game	I-Application
,	O
scientist	O
Robin	O
Ayou	O
smuggles	O
herself	O
onto	O
planet	O
4546B	O
in	O
a	O
frozen	O
biome	O
named	O
"	O
Sector	O
Zero	O
"	O
in	O
order	O
to	O
investigate	O
the	O
circumstances	O
of	O
her	O
sister	O
Samantha	O
's	O
death	O
,	O
which	O
Alterra	O
claims	O
was	O
a	O
result	O
of	O
"	O
employee	O
negligence	O
"	O
.	O
</s>
<s>
Subnautica	B-Application
:	I-Application
Below	I-Application
Zero	I-Application
was	O
initially	O
envisioned	O
as	O
a	O
downloadable	B-Protocol
content	I-Protocol
(	O
DLC	B-Protocol
)	O
pack	O
for	O
the	O
original	O
Subnautica	B-Application
(	O
2018	O
)	O
,	O
though	O
its	O
scope	O
eventually	O
expanded	O
significantly	O
,	O
prompting	O
Unknown	O
Worlds	O
to	O
release	O
Below	O
Zero	O
as	O
a	O
standalone	O
product	O
.	O
</s>
<s>
It	O
is	O
considered	O
to	O
be	O
a	O
sequel	O
to	O
Subnautica	B-Application
.	O
</s>
<s>
Announced	O
in	O
August	O
2018	O
,	O
the	O
game	O
was	O
released	O
into	O
early	O
access	O
for	O
macOS	B-Application
and	O
Windows	O
on	O
January	O
30	O
,	O
2019	O
.	O
</s>
<s>
The	O
full	O
game	O
was	O
released	O
for	O
these	O
platforms	O
,	O
along	O
with	O
versions	O
for	O
Nintendo	B-Application
Switch	I-Application
,	O
PlayStation	B-Operating_System
4	I-Operating_System
,	O
PlayStation	B-Device
5	I-Device
,	O
Xbox	B-Device
One	I-Device
,	O
and	O
Xbox	B-Device
Series	I-Device
X/S	I-Device
,	O
on	O
May	O
14	O
,	O
2021	O
.	O
</s>
<s>
Subnautica	B-Application
:	I-Application
Below	I-Application
Zero	I-Application
received	O
"	O
generally	O
favorable	O
reviews	O
"	O
according	O
to	O
Metacritic	O
.	O
</s>
