Absorption (吸収) is a technique used by certain characters, and a form of fusion. Absorption is usually used when a victim possesses certain strengths or abilities that an attacker desires. The technique involves either engulfing a victim completely, or using a part of their body to suck the victim into their body, thus gaining their power and abilities.
Majin Buu's absorption
Super Buu fully engulfs and takes an opponent into his body, causing an increase in his physical and/or mental powers. Buu usually has a severed body part liquefy, or he has a piece of skin fall off of his body. The goo will then sneak up behind the person, and stretch itself to be large enough to accommodate the target. It will then leap onto the person, and try to smother as much of the target as it can on the first strike to make the capture easier. If Buu is lucky, it will completely cover the person directly on the first leap. Once the goo is on the person, it will quickly cover up any part of the person that was not covered when it first leaped. Once the target is completely covered, the goo will squeeze and solidify, trapping the person. It is seemingly impossible to escape it, no matter what the circumstances (such as Piccolo, who the goo took a long time to cover due to his armor and Gotenks' constant struggle with the goo) but with the possible exception of Vegito who allowed himself to be absorbed, and used a Saiyan Shield to protect himself.
Buu will then raise his finger up, and the goo will then launch up into the air with the person inside of it. The goo will then fly straight into Buu and cover him. During the transformation, Buu will become liquefied himself, meaning that he takes over the goo and has surrounded the person with his own liquefied body. He then begins to mold back into solid form, making sure the person is in the center of the goo. The person is shrunken and is put inside Buu's body in a pod. The transformation is long and usually accompanied by loud moans and groans, most prominently heard when Buu absorbs Gotenks and Piccolo. As Buu is absorbing those two, the Fusion vest can clearly be seen forming roughly on Buu's shoulder showing that Buu is using Gotenks as his main power source and whether these sounds are of Buu struggling to absorb two beings at once or just because of all the power that Gotenks has or that Gotenks is still struggling during the absorption.
Unlike Cell, who took in life essence only through his tail, Buu can perform this technique with any part of his body, even a severed limb, or he can simply liquefy his whole body and cover the victim with himself. When absorbing another being, Buu always takes qualities of their outward appearance as well. In the case of the Z Fighters, he always donned a garment of his strongest victim (first Gotenks' vest, followed by Piccolo's cape, and finally the top of Gohan's martial arts uniform). He also gains knowledge of their attacks, like Piccolo's Special Beam Cannon, Gotenks' Galactic Donut and Super Ghost Kamikaze Attack, and Gohan's Kamehameha.
Cell is able to absorb energy or even entire beings through his tail, gaining all of the strength of the person he has absorbed. He has two methods of absorption: the first method is to stab his target with the sharp end of his tail. The tail will then extract all of the organic matter of the victim, leaving the clothing behind. The process appears quite agonizing for the victim. According to Cell, this is how he feeds, as he often licks his lips before consuming a large population or an android. He also states that the more he eats, the hungrier and stronger he becomes. While this form of absorption is unusable on mechanical beings and is much less versatile in comparison to Majin Buu's absorption technique, Cell's absorption via stabbing the victim with his tail is the only form of absorption used in the series that makes the victim completely unable to be freed, due to the victim being broken down into genetic material and then integrated directly into Cell's body. During his first confrontation with Piccolo, acid dripped from his stinger, indicating that the absorption might happen by injecting a digestive enzyme into the victim and absorbing the dissolving genetic extract.
In addition to the above variation, Cell has a second method of absorption in which he will absorb a person whole. Cell will open up the pointed end of his stinger, and it will become a giant sucker. Cell will bring the sucker down on the person, and the sucker will suck them through Cell's tail into his body. The person will then be held unconscious in Cell's body. This method was designed for Android 17 and Android 18, who, due to not being completely organic (as they were human before Dr. Gero modified them), had to be absorbed whole. This is Cell's preferred method, as it gives him full power, and is the only way for him to advance to his Semi-Perfect and Perfect forms, respectively attained by absorbing one and both of the cyborgs. Cell's absorption through his tail is named Tail Trap in the Dragon Ball Z Collectible Card Game.
After Cell's self-destruction, it was revealed that his cells had remembered the perfect form that he had achieved by absorbing Androids 17 and 18, and even though he no longer had the androids inside of him, he was able to regenerate into his final, Super Perfect form. Even though Cell's tail retracted after becoming Super Perfect Cell, it is shown in Dragon Ball GT that Cell can still bring his stinger out and absorb other people using this technique, though Goku was able to escape when Cell absorbed him. The tail, like any part of his body, can also regenerate when removed, making it impossible for him to be deprived of his absorption capabilities without him or his target being killed first.
Big Gete Star's absorption
The Big Gete Star is able to absorb and incorporate things into itself to upgrade itself. It started as a sentient computer chip but absorbed an entire graveyard of abandoned satellites, and later what remained of Cooler in order to upgrade itself. In a special scenarion in the Nintendo DS game Dragon Ball Z: Supersonic Warriors 2, it also integrates Android 17 and Android 18 into itself until Cell steals them.
Hirudegarn's method of absorption is to raise his gigantic tail, open it and trap his victims with threads. He then sucks their energy out of their bodies and into his tail up into his head, while growing stronger with each second. He uses this technique to absorb humans in Dragon Ball Z: Wrath of the Dragon.
Luud absorbs the people he turned into dolls in order to collect their energy. To do so, he creates winds that bring the doll to his mouth. In the arcade game Dragon Ball Heroes, Luud instead fires a mouth blast that capture his victim and brings him/her to his mouth.
General Rilldo's absorption
General Rilldo is able to absorb the left over parts of Super Mega Cannon Sigma in order to turn into his Hyper-Meta Rilldo form.
Super 17's absorption
In the arcade game Dragon Ball Heroes, Super 17 has exclusive transformations where he absorbs either Android 16 or Cell to increase his power. He is called Super 17 (Android absorbed) and Super 17 (Cell absorbed) respectively. His appearance remains roughly the same, just that his muscles bulk up and, with Cell absorbed, he has black parts similar to those of Perfect Cell on his cheeks, shoulders, chest, and legs.
Naturon Shenron's absorption
Absorbing others is the primary tactic of Naturon Shenron, the Seven-Star Shadow Dragon. His absorption technique involves releasing a blue aura from his corrupted Dragon Ball, which draws a nearby organism into his body. In his only on-screen absorption, he reverted to his Dragon Ball form to trick his enemies into thinking he was beaten.
After absorbing a victim, Naturon grows exponentially into a more monstrous version of himself, inheriting small elements of his victim's appearance and some of their abilities. No matter what form he takes, Naturon Shenron always seems to keep his pink nose, as well as his horns, claws, and whiskers (but they change size and color depending on what he has absorbed). The victim remains suspended in Naturon's body, bound by tendrils of flesh, and Naturon can move them through his mass at will. Naturon appears to draw life energy out of his victim to sustain his form, as he claims that he can "burn out" his host bodies with sufficient exertion. The only way to remove Naturon's power is to either forcibly remove his victim or to "burn it out" with prolonged combat, after which Naturon will be forced to expel his victim and seek a new one.
- In Dragon Ball Z: Budokai Tenkaichi 2, Baby's ability to possess people is referred to as absorption. With the pre-battle summary saying Baby absorbed many of Goku's friends, and with Baby stating that he absorbed Vegeta.