Gaster (also: Guster, Gasder) was a Hyper-Zoanoid in Guyver, and a member of the Hyper-Zoanoid Elite Squad, known as the “Hyper-Zoanoid Team Five”. He was created by Dr. Barcas, as were the rest of the Hyper-Zoanoid Team Five members, and possessed the abilities to not only grow organic missiles, but also to spray a composite explosive liquid at his opponents. Gaster was a Bio-Missile Enabled type of Hyper-Zoanoid who was able to produce and guide his missiles himself organically and telepathically.
He was optimized with the best technology available at Chronos at that time, as were the other members of the team, to be the "Best of the Best!" and was said to have the potential power of destroying not only a Guyver, but its control medal as well. Equipped with two hose-like nozzles, which spray highly combustible liquids he secretes from internal glands, and the ability to sprout bone-like projectiles each carrying these combustible liquids, this Hyper-Zoanoid is very dangerous in both close quarter combat, and in long range battles.
Gaster appears to be a stocky, middle-aged Euro-American man while in his human form and possesses a physically strong reptilian-like build, with most of his muscle built towards his bio-organic missile pouches, in his Hyper-Zoanoid form. Gaster wears the standard Hyper-Zoanoid uniform, has long, wild red hair (suggesting he may be a descendant from the British isles), pointed ears and broad facial features.
His Hyper-Zoanoid form is somewhat reptile-like, and seems to be based off of some sort of bat; his head being fairly small with large pointed bat-like ears. He also sports large iguana-like neck spines. His purplish-red skin is lined with yellow conspicuous vessels that most likely contain and distribute the various explosive liquids that fuel his signature abilities. Each arm is noticeably bloated, tapering into a nozzle from which his explosive liquids are sprayed. His most distinctive features, however, are the two massive, sagging sacks that rest upon either shoulder, each covered in crater-like orifices that contain his signature bio-missiles.
Gaster is both boastful and eager to show off his abilities as well as his powers. He often volunteers to go on dangerous missions or to use his abilities. He usually uses his missiles to completely eradicate his or Chronos's enemies without taking prisoners. However, he is also collected while on missions, and although he is more than willing to use his power to win Team Five's battles he will only fire his missiles if he has permission to do so and the devastation would be somewhat limited. Gaster has also been seen to believe that nothing could withstand the power of his missiles and was relatively shocked to find Aptom had not only survived his missile barrage but had escaped unscathed.
Though Gaster is incredibly powerful, and dangerous, he has been seen to take his enemies very seriously and even frightened by their threats. Though not a coward, Gaster has been seen to be relatively afraid of Aptom and his powers, and was afraid to be left alone by himself; revealing Gaster to be both cautious, nervous and aware of his surroundings. Gaster was considered to be vital for Team Five and was likewise close with his companions. Gaster would often come to the aid of his fellow Team members, or would seek help from them himself if he needed it.
Gaster has been seen to care for his comrades, and was seen firing all of his missiles at Aptom, after he had asbsorbed Elegen and wounded Derzerb. From that point on Gaster would remain cautious of Aptom, fearing for his life and becoming somewhat paranoid that Aptom was going to fulfill his promise and absorb him next; something that, to Gaster's horror, came true.
Mt. Minikami arc
In The Guyver - Bio-Booster Armor OVA, Gaster is a Hyper-Zoanoid and still a member of the Hyper-Zoanoid Team Five; and is both incredibly powerful and dangerous. He was still created by Dr. Barcas, but unlike the anime or the manga, Gaster was one of Richard Guyot's subordinates, instead of Dr. Barcas's, and made his debut with the rest of his team, when they escorted Guyot to Chronos Japan. Gaster later was seen questioning Agito's authority and position, speaking with his team leader ZX-Tole about him, and was surprised to find that he held a position as a future candidate as commander.
Later Gaster was a part of the Chronos operation that took place at Sho Fukamachi's high school in an attempt to capture and/or kill Guyver I, like the rest of his team. The attack on the school took place during school hours and as a result many students were killed while others were rounded up by Chronos agents and were brainwashed of the event. However, despite this the mission was a failure. The Hyper-Zoanoid's attempted to destroy the school in hopes of leaving no evidence behind of Chronos's existence, killing everyone they came into contact with or who knew of the Guyver's existence. The attack was also designed to draw out Guyver I from the school to fight the Hyper-Zoanoids.After nearly five minutes of attacking the school, Sho took the bait and proceeded to battle both Elegen and Derzerb. Guyver I kicked Elegen in the head knocking him to the ground and charged at Derzerb, attempting to punch him. However, Derzerb caught his punch and began to crush his fist. Guyver I was quickly overwhelmed and beaten back by both Elegen's electric shock and Derzerb's raw strength. After being pushed through the school building by Derzerb, Guyver I came face to face with Gaster and suffered a direct hit to his left forearm by his liquid missile, losing his bivration blade in the process. Gaster mocked Guyver I, claiming he was going to "End his misery." and end his life. Gaster continued to fire his missiles at Guyver I, and blew him across the school grounds, destroying the building and the school yard as well. However, Thancrus stopped Gaster from killing Guyver I with his liquid missiles, claiming "It [Gaster's Missile] would destroy the Control Medal." Thancrus then proceeded to fight Guyver I in hand-to-hand combat. After slicing Guyver I, severely wounding him in the process, Thancrus quickly moved in, in an attempt to cut off Guyver I's head. However, Guyver I blocked Thancrus's high-frequency sword with his own, resulting in a High-Frequency Lock, and shattered the nearby glass. Alarmed that the Guyver I had his own vibration swords, Thancrus jumped backwards to gain some distance from Guyver I and in preparation to begin his own counterattack when he was disintegrated by Guyver III's Mega-Smasher.
Enraged, by this turn of events Gaster fired all of his missiles at Guyver III, in an attempt to completely obliterate him, for interferring with their battle. However, Guyver III easily destroyed Gaster's missiles with his sonic emitter, stunning all of the Hyper-Zoanoids and shocking Gaster. Guyver III then gave instructions, albeit telepathically, to Guyver I to attack Gaster; where his liquid supply was stored. Guyver I then rose from the ground, surprising all present, and began to attack Gaster who was forced on the defensive. ZX-Tole, seeing what was happening prepared to fire at Guyver I in an attempt to assist Gaster; but was held at bay by Guyver III firing his Head Beam at him.
Gaster held his ground, while spraying his Liquid Spray at Guyver I, keeping him at bay. However, Guyver III told Guyver I (by telepathy) that by focusing his thoughts and by using the metallic orb on his waste he would be able to achieve levitation. Soon Guyver I took the air, surprising all, and rushed down toward Gaster; slicing open his Liquid Storage and mixing the liquids together all over his body. Gaster soon met his demise, exploding violently from his own power.
Powers & Abilities
Super-Strength: While it is unknown how powerful Gaster is, he has been seen to hold his own while being forced to fighting against Derzerb, and wasn't wounded in the processes.
Liquid Spray: Gaster has two hose like tubes on both of his wrists, each spraying one of the combustible liquids forward. Gaster can use this for his own protection and to keep his opponents at a distance when he is confronted in close quarter combat.
Liquid Storage: Gaster's massive shoulder pods house stacks of chemical glands which continuously produce two components of an explosive, similar to the earlier Hyper-Zoanoid Panadyne. Either element is inert when separate, but if they are mixed, they immediately combust.
Liquid Missiles: Gaster has a total of eighteen missiles, which he can grow with remarkable rapidity, and aren't just rocket-propelled grenades; but rather guided missiles. Small slits on their sides act as exhausts, directing their flight and he can even control them telepathically.
Telepathic Guidance: The crown on Gaster's head functions as an air-and-land search radar, and his huge ears function as object sensors. He acquires his targets using these sensory organs and through the spines on his back; he can easily guide his missiles directly to his target.