<s>
Dota	B-Application
Underlords	I-Application
is	O
a	O
2020	O
auto	O
battler	O
game	O
developed	O
and	O
published	O
by	O
Valve	O
.	O
</s>
<s>
The	O
game	O
is	O
based	O
on	O
a	O
popular	O
Dota	B-Application
2	I-Application
community-created	O
game	O
mode	O
called	O
Dota	B-Operating_System
Auto	I-Operating_System
Chess	I-Operating_System
,	O
which	O
was	O
released	O
in	O
January	O
2019	O
.	O
</s>
<s>
Dota	B-Application
Underlords	I-Application
first	O
released	O
in	O
early	O
access	O
in	O
June	O
2019	O
before	O
officially	O
releasing	O
on	O
February	O
25	O
,	O
2020	O
,	O
for	O
Android	B-Application
,	O
iOS	B-Application
,	O
macOS	B-Application
,	O
Linux	B-Application
,	O
and	O
Windows	O
.	O
</s>
<s>
The	O
game	O
is	O
free	O
to	O
play	O
and	O
features	O
cross-platform	B-Application
play	I-Application
.	O
</s>
<s>
Dota	B-Application
Underlords	I-Application
is	O
an	O
auto	O
battler	O
,	O
a	O
chess-inspired	O
competitive	O
strategy	B-Application
game	I-Application
,	O
where	O
players	O
place	O
characters	O
,	O
known	O
as	O
heroes	O
,	O
on	O
an	O
8x8	O
grid-shaped	O
battlefield	O
.	O
</s>
<s>
Dota	B-Application
Underlords	I-Application
was	O
developed	O
and	O
published	O
by	O
Valve	O
for	O
Android	B-Application
,	O
iOS	B-Application
,	O
macOS	B-Application
,	O
Linux	B-Application
,	O
and	O
Windows	O
.	O
</s>
<s>
It	O
is	O
based	O
on	O
Dota	B-Operating_System
Auto	I-Operating_System
Chess	I-Operating_System
,	O
a	O
popular	O
community	O
created	O
game	O
mode	O
within	O
Dota	B-Application
2	I-Application
,	O
a	O
game	O
they	O
also	O
developed	O
.	O
</s>
<s>
Following	O
Dota	B-Operating_System
Auto	I-Operating_System
Chess	I-Operating_System
release	O
in	O
January	O
2019	O
,	O
it	O
quickly	O
became	O
a	O
phenomenon	O
,	O
having	O
over	O
seven	O
million	O
players	O
by	O
April	O
2019	O
,	O
Valve	O
had	O
met	O
with	O
the	O
mod	O
's	O
developers	O
,	O
the	O
Chinese-based	O
Drodo	O
Studio	O
,	O
to	O
discuss	O
directly	O
collaborating	O
on	O
a	O
standalone	O
version	O
.	O
</s>
<s>
However	O
,	O
the	O
two	O
companies	O
were	O
unable	O
to	O
come	O
to	O
an	O
agreement	O
,	O
with	O
them	O
both	O
stating	O
that	O
it	O
was	O
in	O
their	O
best	O
interest	O
to	O
develop	O
their	O
own	O
separate	O
games	O
,	O
with	O
Dota	B-Application
Underlords	I-Application
being	O
Valve	O
's	O
project	O
.	O
</s>
<s>
The	O
game	O
was	O
built	O
using	O
Valve	O
's	O
Source	B-Operating_System
2	I-Operating_System
game	O
engine	O
,	O
making	O
it	O
the	O
first	O
game	O
using	O
that	O
engine	O
to	O
be	O
released	O
on	O
mobile	O
platforms	O
.	O
</s>
<s>
Valve	O
announced	O
Dota	B-Application
Underlords	I-Application
in	O
May	O
2019	O
,	O
with	O
it	O
releasing	O
in	O
early	O
access	O
as	O
a	O
free-to-play	O
game	O
on	O
June	O
20	O
,	O
2019	O
.	O
where	O
it	O
saw	O
over	O
1.5	O
million	O
downloads	O
and	O
held	O
a	O
concurrent	O
player	O
count	O
on	O
Steam	B-Application
of	O
over	O
200,000	O
within	O
a	O
few	O
days	O
.	O
</s>
<s>
It	O
features	O
full	O
cross-platform	B-Application
play	I-Application
between	O
its	O
PC	O
and	O
mobile	O
versions	O
,	O
with	O
players	O
able	O
to	O
freely	O
start	O
games	O
on	O
one	O
and	O
finish	O
it	O
on	O
another	O
.	O
</s>
<s>
Polygon	O
called	O
it	O
a	O
clone	O
of	O
Dota	B-Operating_System
Auto	I-Operating_System
Chess	I-Operating_System
,	O
stating	O
that	O
while	O
they	O
thought	O
Underlords	B-Application
was	O
more	O
appealing	O
to	O
new	O
players	O
,	O
the	O
many	O
similarities	O
to	O
the	O
original	O
mod	O
could	O
make	O
it	O
hard	O
for	O
veterans	O
of	O
the	O
genre	O
to	O
see	O
a	O
reason	O
to	O
play	O
Underlords	B-Application
over	O
it	O
.	O
</s>
<s>
Critics	O
also	O
compared	O
and	O
contrasted	O
it	O
with	O
Artifact	B-Application
,	O
another	O
Valve-developed	O
Dota	B-Operating_System
spinoff	O
game	O
released	O
around	O
the	O
same	O
time	O
that	O
was	O
seen	O
as	O
unsuccessful	O
,	O
as	O
well	O
as	O
Teamfight	B-Application
Tactics	I-Application
,	O
the	O
League	B-Application
of	I-Application
Legends	I-Application
take	O
on	O
the	O
genre	O
.	O
</s>
<s>
IGN	O
considered	O
Underlords	B-Application
to	O
be	O
the	O
easiest	O
auto	O
battler	O
to	O
get	O
into	O
as	O
a	O
novice	O
due	O
in	O
part	O
to	O
its	O
user	B-Application
interface	I-Application
.	O
</s>
