- The following stage is only available in the Sharp X68000 remake of Gradius 2 known as Nemesis '90 Kai.
- If you are skillful enough to survive the return trip through the Life Planet and Planet of Fire, you may wind up in the first of two alternate stages. This stage takes place in an asteroid belt, and is often compared with the fifth stage of Salamander.
- Even before you are solidly all the way through the pre-stage, you will begin to encounter chunks of rocks flying through space, which you must successfully dodge. The asteroids which fly through this stage come in a couple of sizes, but for the most part they behave like the crystalline rocks which you encounters in the Floating Continent stage.
- Though not nearly as large and fully featured as the continents in the Floating Continent stage, this stage does contain islands of rock where red cannons are situated. They can be attached on top or below rocks, so you must stay mindful of who might shoot at you. Since they are red, they leave power-ups behind, fairly close to the rock, which can also be challenging to collect if you have too much speed.
- Throughout the stage, both enemies and more rocks will fly on to the stage, some floating off in no particular direction, while other fly straight towards you. As a result, you want to keep moving to avoid the obstacles that are headed in your direction, but stay aware of the direction of other rocks that aren't headed straight at you. You don't want to position yourself somewhere where you will get caught between a few rocks and the edge of the screen with no means of escape.
- Eventually, you will reach a place where a set of eight small enemies known as Zabus suddenly appear in a ring around your location. Once fully materialized, they expand outward briefly before changing course and dashing back to the point of origin and beyond. Keep moving away from the location where they surrounded you and fire continuously to destroy a few and clear a path to safety.
- Beyond this point, there are a few more islands with a multitude of cannons stationed around. The appearance of asteroids will hit their peak, and you must constantly move around to avoid the asteroids hurtling toward you at high speed, while monitoring the screen for indications of further asteroids that might box you into one section of the screen and ultimately cause you to crash. Collecting power-ups is advisable only when it is truly safe to do so.
The boss of this stage, known unofficially as "Big Core Mk. II" is not a huge challenge in comparison to some of the bosses you've already faced. It contains two core, both of which must be unshielded and destroyed in order to advance. The boss has two phases. In the first phase, the boss is invincible as it moves up and down firing one laser from its central cannon, and four missiles from around the sides. While the laser beam must be avoided, the missiles can be destroyed with your own weapons. In the second phase, the ship comes to a stop and its shielding expands exposing the cores behind it. When the shielding is fully extended, it fires Ripple beams to the left. It only during this time that the ship in vulnerable to attack, although with Lasers and enough Options, you can overwhelm the core shields very easily and destroy the ship entirely before it can fire off any Ripples.