Ultimate UFO is a boss in Stage 5-3, Canonical Genetic Code.
Attack pattern[]
Ultimate UFO introduces itself immediately by flying by the player, in an invulnerable state. The player then starts flying around the top of the UFO, destroying the many laser-firing pillars around it. Once the top of it is reached, Progressive-UFO is spawned and must be defeated. After its defeat, the player moves away and the music changes, The player then moves to a different part of the UFO, featur
ing a massive cannon and several spinning pillars. After these are navigated, the player navigates to the core of the UFO, which shoots tracking lasers at you. After the core has been dealt sufficient damage, it breaks, revealing a hole in the UFO. The player flies through it and the UFO can be seen moving away - possibly exploding - as the boss outro plays.