Oil Ocean Zone

From Sonic Retro

Oil Ocean Zone

Oil Ocean Zone

Oil Ocean Zone

Seventh level, Sonic the Hedgehog 2 Number of Acts: 2 Level theme: industrial Boss: Submarine Eggman II Maximum Rings, Act 1: 207 + 50 Maximum Rings, Act 2: 183 + 80 Music: Level icon:

Oil Ocean Zone is the seventh zone in Sonic 2. The entirety of this zone takes place across a massive sea of oil dumped by Robotnik which you'll sink into and die if you stand in it, though it's possible to jump out of it. Other features include slippery oil slides like the water slides featured in the Labyrinth Zone, fans that block you from certain paths like in Star Light Zone but can also lift you into the air, networks of balloon-like launchers that take you somewhere, and bursting steam vents that can give you a lift to high places. In the Simon Wai prototype of Sonic 2, Oil Ocean Zone uses the CNZ 2 player music (albeit at a slightly slower tempo). The current music for OOZ was in the Simon Wai prototype, but it was unused and it had a much slower tempo.

Earlier versions of this zone featured a smaller version of the rolling ball that was cut out of Green Hill Zone but operated by a button, and while it's nowhere to be found in the final release of Sonic 2 it can be placed via debug mode.

1 Instruction Manual Description
2 Sonic Team Commentary (from Sonic Jam Strategy Guide)
3 Enemies
4 Technical Information
- 4.1 Technical notes

Instruction Manual Description

“	Robotnik's refineries are pumping at full steam. Crude oil has turned the ocean black! Can Sonic keep his footing on the slippery catwalks and bursting steam vents?	„
—Sonic 2 US Manual, p. 15

Sonic Team Commentary (from Sonic Jam Strategy Guide)

“	This stage was made by Tom on the SOA staff, it was amazing what could be made with the Mega Drive at the time. But if the Sonicness of it wasn't coming through, sometimes the artist had a taste for darker color schemes, we would fix up certain pieces of it.	„
—Yuji Naka

Enemies

Octus - Octopus enemy, levitates and fires a missile when Sonic approaches.
Aquis - Seahorse enemy, floats around quickly, firing globules of oil at Sonic.

Technical Information

Offset	Description
0A	Oil Ocean Zone level value
$2CE2	OOZ Palette (0E)
$CC66	OOZ layer deformation info
$400C8	OOZ animated pattern load cue (4)
$405B6	OOZ misc sprite mappings (empty)
$420E8	HPZ/OOZ object debug list
$45100	OOZ primary 16x16 collision index
$47404	OOZ act 1 level layout
$47784	OOZ act 2 level layout
$A3364	OOZ 16x16 block mappings
$A4204	OOZ main level patterns
$A6384	OOZ 128x128 block mappings
$E5260	OOZ act 1 ring locations
$E5422	OOZ act 2 ring locations
$E8DA0	OOZ act 1 sprite locations
$E9214	OOZ act 2 sprite locations

Technical notes

Oil Ocean's "sinking pool" mechanic was reused in Marble Garden Zone, though it's not nearly as expansive there.

In this zone, the ground is supported by numerous small pillars that extend down to the oil, but not all the way. Because of this, the player can Spin Dash in the oil while standing against one of these pillars to go under it. In this way, it's possible to travel at the very bottom across the whole stage.

Sonic the Hedgehog 2 (16-bit)

Sonic 2