Nameless is the final boss of the console versions of Space Invaders Infinity Gene, appearing in Stage 5-6, Cleavage.
Nameless appears as a 2D circle with nothing inside, Nameless will shoot lasers out of all sides of its body until it is destroyed. Destroying these lasers will cause them to become "Seeds," and then home into Nameless, harming it. This sound of these lasers being converted and hitting Nameless itself emulate that of the original Space Invaders.

It appears in the center of the grid sphere in the background of Cleavage, and the beams emerging from its body seem to be holding the sphere together.
Biological Connections[]
Many aspects of Space Invaders Infinity Gene are references to biology, be it enemy designs or level names. To this Nameless is no exception, however, with its abstract nature and literal lack of a name, this connection is difficult to pin down.
First of all, Nameless is almost definitely connected to reproduction in some way. The grid pattern on the sphere and the name of the stage connect the boss to embryonic development in some way.
One possible interpretation of Nameless is as the nucleus of an embryonic cell, as the sphere surrounding the boss may be representative of a cell membrane. Another interpretation of Nameless is that the boss itself is an ovum, and the Seeds that fly back to it are sperm. The primary support for this theory is the name and silhouette of the Seeds themselves, vaguely resembling an (admittedly abstract) sperm cell. The name "Seed" (originating from the Evolution Theory Soundtrack booklet) is the literal translation of the Greek word "sperma." With this in mind, it's easy to reason that Nameless itself is the egg cell that sperm fertilize, and by extension its "death" is merely the beginning of a new organism.
Extrapolating on this idea further, Back Mutation may be allegorical to the start of newer games in the franchise, descended from Infinity Gene. Interestingly, the Groove Coaster franchise fits this idea very well, beginning as an "Infinity Gene Project," before developing into a series of its own. In this sense, the games themselves could be considered organisms, changing, developing, and reproducing, also representative of the initial vision of Infinity Gene to "evolve" the Space Invaders franchise. Notably, the track "Lifegame" plays over the credits, playing into the idea that the game is alive.
Strategy[]
There are 2 efficient ways to destroy Nameless.
- Equip a ship that destroys from a large radius. (e.g. Gravity, Field, Wave) and shoot at Nameless to destroy it quickly.
- Equip a short range weapon, find a spot where the player does not hit the lasers and hold the fire button until Nameless is destroyed.