|“||Samus. The wavelength of that monster's cry is driving the other creatures into a frenzy - they've grown markedly more aggressive. It appears to be hiding in Sector 3 now. If you run into that thing, hit it with your Plasma Beam. You've got to take it down!||„|
Ridley's second form takes the appearance of a large, purple, lizard-like creature with white feathers sprouting from its back. The creature uses its long, muscular legs to dart around with great speed and force. Sharp talons tip the ends of the creature's feet, coupled with a long, segmented tail that serves both to provide the creature balance and as a weapon; it is tipped with a sharp blade-like growth which can be used to strike and impale enemy targets.
The hardy skin of the Mystery Creature deflects certain projectiles like bullets with ease. Green extremities appear on the skin of the face, shoulders and limbs, where the hide appears to be toughest. Areas which are especially vulnerable to attack are the mouth, the tip of the tail, and underside, where the skin is weakest. Strange growths at the top of the shoulders appear to be vestigial wings, although as the adult Ridley possesses fully functional wings, they could be the emergence of these rather than their remains.
The skull of the creature is long and narrow, and the jaw is embedded with razor-sharp teeth which are perfect for pinning down and ripping apart prey. Large, orange eyes are located near the front of the skull, where most predatory creatures' eyes are. It seems to possess a great deal of flexibility and can swivel a great deal, enabling it to see at angles which would not normally be possible if facing a certain direction. Translucent eyelids also enable the creature to see while blinking, to allow vision of foes at all times. Finally, an unusually long tongue situated between the teeth often hangs out of the mouth.
Samus sees the creature attacking the 07th Platoon in the Biosphere Test Area from the Exam Center and runs to save them. However, when Samus arrives, the creature seems to be waiting specifically for her, hiding out of Samus' view and ambushes her. It pins Samus down and attacks her with its tail and sharp teeth. The soldiers try to help her, but they are distracted by swarms of enemies the creature summons, including Reos and Griptians. Samus attacks the lizard's tail as it attempts to strike her head. Eventually Anthony Higgs fires a stream of plasma from his Plasma Gun at the creature, wounding and knocking it off Samus, causing the creature to go into convulsions for a few seconds. Anthony attempts to shoot at again, but it escapes by crashing through a wall which was disguised by the holographic scenery. Soon after the 07th Platoon finds Lyle Smithsonian's body ripped into shreds, Samus follows a trail of green blood and finds the husk of the little white creature she encountered earlier, which implies that the Mystery Creature killed and ate Lyle's body after it molted from its previous form, helping it grow larger.
Samus is given orders to chase the monster, but finds only a trail of blood. Adam instructs Samus to follow the creature to Sector 3, the Pyrosphere, though is shortly redirected to hunt for BOTTLE SHIP survivors in the Cryosphere instead. Unfortunately during Samus' time in the arctic area, the beast's cries cause the other creatures to become extremely aggressive.
On a later journey to the Pyrosphere, Samus discovers the creature's remains as an empty husk stuck to a wall above a door, its back ripped open from the inside. Samus continues through the room, where she thinks that she will encounter the next stage in the creature's life. Samus meets up with Anthony again, where he is trying to fight an unseen flying creature. Samus eventually obtains a clear view of the creature and realizes that the purple lizard (and its previous form), was Ridley all along.
It is unknown if Ridley's clone retained its memory of his predecessor and of his rivalry with Samus Aran. It is interesting to note that the creature focused most of its attention on her during its earlier battle, though this can be seen as the monster perceiving her as the greater threat.
The battle with the Mystery Creature is one of the few battles in which Samus is locked in first person perspective, the others being a short moment while battling the Queen Metroid, and near the end of the game when Samus is battling MB and the Desbrachians. The Mystery Creature pins Samus down and attempts to stab her with its tail as well as occasionally biting at her head. To drive off the beast, Samus must shoot Missiles at its tail, the creature's only weak spot. This is somewhat difficult, as the Mystery Creature keeps the appendage in constant motion. After the tail takes significant damage, Anthony will blast the creature off Samus.
- Using a SenseMove against the creature shows Samus merely throwing her body out of the creature's reach, due to the circumstances of the battle.
- Even in his infant and adolescent stages, Ridley displays signs of high intelligence. In his second form, he had prepared an ambush for Samus, (potentially) gave orders to other bioforms and knew when to fight or retreat in battle. After he was shot by Anthony, Ridley appeared ready to attack, until he noticed that Anthony could fire the weapon again, in which he quickly retreated.
- Ironically, in the battle with the Mystery Creature, the tail is the creature's only weak spot, while in all of Ridley's 2-D (excluding the original Metroid) and other 3-D appearances, it is one of his, or only, invulnerable spot(s). It's possible that this early vulnerability is the reason Ridley shields this area so thickly in his later stages.
- The creature's tail and back-growths heavily resemble the Xenomorphs from Alien, a series which inspired Metroid.
- The way that Little birdie and this creature "molted" is also very similar to the way the Xenomorph transfers to the next stage of life.
- This creature seemed to have gone through an extreme growth spurt in a short amount of time after its molt, since its former shell is near a trail of green blood that leads to the corpse of Lyle Smithsonian in the same area where it battles Samus and the other members of the 07th Platoon. Additionally, the unlockable artwork of the Mystery Creature portrays a very small version of the lizard crawling out of the shell of Little birdie.
- An example foreshadowing the identity of the creature is the music for the Mystery Creature battle: a small segment of it contains a similar melody of Ridley's battle theme.
- When Samus returns to the BOTTLE SHIP after it has been taken under Federation control, the Mystery Creature's husk remains on the wall.
- Its trophy in Super Smash Bros. for the Wii U in both the NTSC-U and to a lesser extent PAL versions imply that Ridley's antagonism of Samus was partially rooted in his role in Samus's parents death.
"What once was a cute little bird has changed into a lizard-like creature. It still has some white feathers from its previous form, but that's where the similarities end. Is there something in its blood that drives it to confront Samus whenever possible? Her parents were Ridley's victims, after all."
"If Little Birdie is Ridley's cute baby years, this must be his awkward teenage phase. The feathers on his back are the only real clue that it's the same creature. Is there something in Ridley's genes that make him hate Samus so much? The original Ridley killed her parents, and now this one is out to get her too!"
Little Birdie • Mystery Creature • Clone • Neo-Ridley
Fake Ridley • Ridley-2 • Ice Ridley
Ultrathermal Flamestrike Projector
Multi-Missile System • Phazon-enhanced armorskin
Vs. Meta Ridley/Meta Ridley • Omega Ridley