<s>
Nebulus	B-Application
is	O
a	O
platform	O
game	O
created	O
by	O
John	O
M	O
.	O
Phillips	O
and	O
published	O
by	O
Hewson	O
Consultants	O
in	O
the	O
late	O
1980s	O
for	O
home	O
computer	O
systems	O
.	O
</s>
<s>
International	O
releases	O
and	O
ports	O
were	O
known	O
by	O
various	O
other	O
names	O
:	O
Castelian	B-Application
,	O
,	O
Subline	O
,	O
and	O
Tower	B-Application
Toppler	I-Application
.	O
</s>
<s>
Nebulus	B-Application
was	O
followed	O
by	O
the	O
lesser-known	O
Nebulus	B-Application
2	O
for	O
the	O
Amiga	B-Device
in	O
the	O
1990s	O
.	O
</s>
<s>
Nebulus	B-Application
is	O
a	O
platform	O
game	O
.	O
</s>
<s>
Pogo	O
then	O
boards	O
his	O
submarine	O
and	O
enters	O
a	O
bonus	O
stage	O
(	O
in	O
some	O
versions	O
,	O
but	O
not	O
for	O
example	O
in	O
the	O
ZX	B-Operating_System
Spectrum	I-Operating_System
version	O
)	O
,	O
where	O
he	O
can	O
shoot	O
various	O
kinds	O
of	O
fish	O
to	O
score	O
bonus	O
points	O
.	O
</s>
<s>
The	O
game	O
was	O
originally	O
released	O
by	O
Hewson	O
for	O
the	O
ZX	B-Operating_System
Spectrum	I-Operating_System
,	O
Amstrad	B-Device
CPC	I-Device
,	O
Commodore	O
64	O
,	O
Commodore	B-Device
Amiga	I-Device
,	O
Atari	B-Device
ST	I-Device
and	O
Acorn	B-Device
Archimedes	I-Device
.	O
</s>
<s>
The	O
US	O
version	O
,	O
which	O
was	O
published	O
by	O
U.S.	O
Gold	O
,	O
was	O
released	O
under	O
the	O
title	O
Tower	B-Application
Toppler	I-Application
.	O
</s>
<s>
A	O
version	O
for	O
the	O
Atari	B-General_Concept
7800	I-General_Concept
was	O
also	O
released	O
with	O
this	O
title	O
.	O
</s>
<s>
The	O
Game	B-Device
Boy	I-Device
and	O
Nintendo	O
Entertainment	O
System	O
versions	O
of	O
Castelian	B-Application
were	O
developed	O
by	O
Bits	O
Studios	O
and	O
released	O
in	O
the	O
United	O
States	O
by	O
Triffix	O
and	O
in	O
Japan	O
by	O
Hiro	O
Entertainment	O
;	O
in	O
these	O
,	O
the	O
lead	O
character	O
is	O
called	O
Julius	O
.	O
</s>
<s>
The	O
Game	B-Device
Boy	I-Device
and	O
Nintendo	O
versions	O
were	O
later	O
released	O
in	O
Japan	O
as	O
Kyoro	O
Chan	O
Land	O
,	O
which	O
replaced	O
Julius	O
with	O
Kyorochan	O
,	O
jewels	O
with	O
Chocoballs	O
,	O
altered	O
the	O
enemy	O
graphics	O
and	O
(	O
in	O
the	O
Famicom	O
version	O
)	O
added	O
a	O
password	O
system	O
and	O
a	O
pause	O
feature	O
.	O
</s>
<s>
The	O
Nintendo	O
versions	O
were	O
composed	O
by	O
David	O
Whittaker	O
,	O
and	O
the	O
title	O
songs	O
were	O
covered	O
by	O
Whittaker	O
from	O
the	O
original	O
Tower	B-Application
Toppler	I-Application
game	O
's	O
title	O
screen	O
.	O
</s>
<s>
In	O
2004	B-Application
it	O
was	O
re-released	O
on	O
the	O
C64	B-Device
Direct-to-TV	I-Device
.	O
</s>
<s>
The	O
C64	B-Device
DTV	I-Device
version	O
made	O
comeback	O
on	O
the	B-Operating_System
Wii	I-Operating_System
's	O
Virtual	B-Application
Console	I-Application
download	O
service	O
in	O
Europe	O
on	O
June	O
13	O
,	O
2008	O
and	O
later	O
in	O
North	O
America	O
on	O
May	O
4	O
,	O
2009	O
.	O
</s>
<s>
The	O
Atari	B-Device
8-bit	I-Device
version	O
was	O
being	O
developed	O
around	O
1988	O
by	O
the	O
author	O
of	O
the	O
Atari	B-General_Concept
7800	I-General_Concept
port	O
,	O
and	O
was	O
intended	O
to	O
be	O
released	O
by	O
Atari	O
Corporation	O
for	O
the	O
XE	B-General_Concept
Game	I-General_Concept
System	I-General_Concept
.	O
</s>
<s>
stated	O
that	O
the	O
Commodore	O
64	O
version	O
of	O
Tower	B-Application
Toppler	I-Application
had	O
"	O
good	O
arcade	O
action	O
,	O
with	O
well-executed	O
graphics	O
"	O
.	O
</s>
<s>
The	O
ZX	B-Operating_System
Spectrum	I-Operating_System
version	O
was	O
rated	O
number	O
30	O
in	O
the	O
Your	O
Sinclair	O
Official	O
Top	O
100	O
Games	O
of	O
All	O
Time	O
.	O
</s>
<s>
The	O
Amiga	B-Device
version	O
was	O
ranked	O
the	O
14th	O
best	O
game	O
of	O
all	O
time	O
by	O
Amiga	B-Device
Power	O
.	O
</s>
