Gradius III/Stage 2

Space flight
The first wave of five arrives from the bottom, and is followed by a wave from the top.

Aqua Illusion (Bubble)
This stage is in a bubble fortress, and features some odd parts. The enemy base will have watery walls on the top and bottom. You will also expect flying waves approaching from behind, in addition to the bubbles arriving ahead of you.

When you see the large blue bubble enter the screen, you may notice an enemy hovering behind you. After a few seconds of waiting, it will charge forward and attempt to steal your options (SNES only).

Tips

 * The most notable part are the bubbles. The bubbles are deadly, but are easy to destroy. They break into smaller ones when shot at, so be careful. Some bubbles are red and give powerups when destroyed, but make sure to take care of the other bubbles before getting the powerups. Keep an eye on the Rugals coming from behind.
 * Hatches and cannons can also be found on the bubbly terrain. Free flying enemies can also be found. Like the bubbles, watch out for other enemies. The enemies from the hatches can fire quite a few bullets, and they can sometimes force you to go for gaps quickly. If so, you may need the Force Field.
 * At the end of the stage, you will see holes in the ceiling and floor(unofficially called Bubble Fighters). Fighters in bubbles will emerge. After a few seconds after spawning, the bubbles break and the enemies track you and attempt to destroy you. Try to let the enemies group up before killing them.

Boss: Bubble Eye
The stage boss is slightly weaker than the previous one.
 * It inflates a bubble on its top or bottom, then breaks it into three smaller bubbles. These smaller projectiles bounce off the top and bottom of the screen.
 * Occasionally, it will create a bubble on the front. This can be destroyed without ill effects.

To damage it, aim for the eye. Your shots will gradually drill a hole to the eye, allowing you to get a clear hit on the core.

SNES Differences
There are hardly any differences, although you might find an Option Hunter.
 * Bubble Eye originally moved regardless of whether he was shot or not. The SNES lacks that part.
 * There is a bonus stage accessible by going into the bottom hole where the bubble enemies appear.