<s>
Tunnels	B-Application
of	I-Application
Doom	I-Application
is	O
a	O
role-playing	O
video	O
game	O
programmed	O
by	O
Kevin	O
Kenney	O
for	O
the	O
TI-99/4A	B-Device
home	O
computer	O
and	O
published	O
by	O
Texas	O
Instruments	O
on	O
December	O
31	O
,	O
1982	O
.	O
</s>
<s>
Upon	O
encountering	O
an	O
enemy	O
,	O
the	O
game	O
transitions	O
to	O
a	O
separate	O
,	O
graphical	O
,	O
overhead	O
battle	O
screen	O
,	O
where	O
a	O
tactical	B-Application
turn-based	I-Application
combat	I-Application
system	O
is	O
used	O
that	O
allows	O
for	O
movement	O
and	O
positioning	O
.	O
</s>
