Evil Containment Wave (魔封波 Mafūba, lit. "Demon's Sealing Wave") is a sealing technique invented by Master Mutaito.
It is designed to seal demons away by sucking them into a container with a special "Demon Seal" on it. The move requires huge stamina and endurance to perform, if user does not have enough life force they will die soon after performing it, despite the success of the technique. This technique, however, can be used on any living organism, regardless if they are evil or not. So this technique can be particularly dangerous if it has befallen to the wrong hands.
Any type of container can be used, as long as it can be sealed shut after the technique has been completed. However, the smaller the container, the harder it is to aim the target into its opening.
The technique can be performed in different ways to get the same result in sealing the target as the move requires delicacy and finesse.
The technique's effects appear to be somewhat traumatizing for the victim as King Piccolo reacted with fear once Roshi revealed to him the rice cooker meant as his prison and that he was capable of using the same technique that defeated him. Future Zamasu, after breaking free, began breathing heavily and was clearly frightened and shaken from the experience. The one exception was when Vegeta was freed by Roshi. Vegeta showed no fear from being sealed. Instead, he was furious, and immediately turned Super Saiyan Blue upon escaping.
One interesting aspect of the technique's usage in Dragon Ball Super, is that the technique was not fatal when performed by either Goku or Future Trunks, similar to how it failed to kill Kami when he used it during the 23rd World Martial Arts Tournament and Tien when he used it during the battle against Piccolo. Presumably if the user is sufficiently powerful like Goku, Future Trunks, Tien, and Kami then the technique can be performed without the user dying as Master Mutaito and Master Roshi did. Despite Goku being powerful it took him a long time to master this technique while Future Trunks semi-successfully did his first try on Zamasu.
The technique is named Mafūba in the Japanese dub, as well as the English translation of the Dragon Ball manga. It is named Evil Containment Wave in the Funimation dub, while it retains its original name, Mafūba, in the Blue Water dub.
After King Piccolo was released from his prison by Emperor Pilaf, he is confronted by Master Roshi. Roshi nearly succeeds in using the Evil Containment Wave to contain King Piccolo again, but misses at the last second and dies shortly afterwards. This attempt was witnessed by Tien Shinhan, who learns the Evil Containment Wave from watching Roshi performing it and practices a scaled-down version of it himself several times. When Tien finally confronts King Piccolo, he is not able to use the technique because his Electric Rice Cooker is cracked, so he is forced to try and defeat King Piccolo of his own power. In the anime Tien does attempt to use the technique, however King Piccolo's son Drum realizes what Tien is attempting and sacrifices himself by jumping in front of the blast. Drum is ensnared and about to be confined to the electronic jar, but King Piccolo quickly destroys it before the attack was successful, releasing Drum from the jar and therefore rendering the Evil Containment Wave useless.
Years later, in the confrontation between Kami and Piccolo Jr., Kami demonstrates his knowledge of the technique and attempts to use it to seal away Piccolo. Piccolo counters by reversing the wave with his Evil Containment Wave Reflection technique, which he is able to use to seal Kami. Neither Piccolo nor Kami die as a result of using the wave, and Kami specifically states that it would be a way for him to get rid of Piccolo without dying himself (their lives were connected so that if one died, the other would as well).
The technique is reintroduced in Dragon Ball Super, when Piccolo suggests the technique to Goku who decides to use it in order to defeat Future Zamasu, who is immortal. Goku is taught the technique by Master Roshi who briefly demonstrates the technique for Goku, whom then practices it all night on Turtle, mastering it by the morning.
In the anime, Future Trunks is forced by Bulma to learn the technique via a recording on her phone of Piccolo using it and only gives him a few minutes to do so as she was going to go and seduce Future Zamasu to buy time for Trunks. Future Trunks manages to learn the technique in record time after watching Piccolo perform the technique, and he successfully seals Future Zamasu inside the urn. However we are taken back to the present where we see an enraged Piccolo learn that Master Roshi forgot to send the paper amulet needed to seal the jar with them. In the future, Future Trunks asks about the seal that Piccolo mentioned in the video but Bulma says she doesn't have it. Trunks attempts to hold it shut himself while Bulma used the machine to go back and get it but it was no use and Zamasu manages to break free, horrified about what just happened to him. In the manga, Goku is the one who uses it against Future Zamasu, sealing the immortal god away in a jar - however he collected the wrong tag from Roshi and so Zamasu breaks free. Considering Zamasu doesn't use Kai Kai to just teleport out of the jar it is likely the Evil Containment Wave's sealing prevented him from doing so.
Master Roshi uses this technique against Dercori in the Tournament of Power. He trapped her inside of a small bottle, and threw it outside of the arena, eliminating her. The technique was seemingly not fatal to Master Roshi. However, when he attempts to use the technique against Frost, Master Roshi has lost almost all of his strength and fails to seal Frost inside the bottle. He tries to use it a third time against Magetta, despite warnings it will cost him his life. Frost intervenes and directs the technique at Vegeta, sealing him instead, but Master Roshi is able to free Vegeta by breaking the bottle.
The Evil Containment Wave is much the same in Dragonball Evolution as in the manga and anime, but with some subtle differences. In the manga, Piccolo is not immobilized while in the wave and is capable of destroying the jar himself. In the movie, it is the jar that is called a "Mafuba", not the attack, and preparing the jar seems to require an overnight ceremony, as opposed to simply taping an "evil containment" sign on the side of the jar.
Video Game Appearances
The technique is Master Roshi's meteor attack in Dragon Ball Z: Ultimate Battle 22, called Meteo Telekinesis in the English version. Roshi yells Mafuba and uses his telekinesis to control and attack his opponent. Shin also uses a similar attack in the game.
In an alt scenario of Dragon Ball Z: Super Gokuden: Kakusei-Hen, Tien used it on Piccolo after learning from Goku that he's the reicarnation of Piccolo after the Triclops asks him who he is, sealing Piccolo in the bottle. Unlike the anime version however, Tien died from using it 
In Dragon Ball Z: Supersonic Warriors, Piccolo uses this against Super Buu at the conclusion of his story mode, when he found that even after merging with King Piccolo (which increased his power to one equal to Super Buu), he could not destroy him. Piccolo does not die by performing the technique (Kami did not die when he originally performed the technique and, at this point, Piccolo is fused with Kami, King Piccolo, and is a Super Namekian, thus would be more than powerful enough to perform it without dying). It is described by Piccolo as a technique to seal away evil that is too powerful to destroy. Piccolo successfully uses it to seal Buu in a bottle and places it within the Hyperbolic Time Chamber as a precaution against Buu's release, with Piccolo remaining guard upon Kami's Lookout; later, in Piccolo's bonus scene, Buu is accidentally released by a dimensionally-displaced Gotenks (a Gotenks from the original, "non-what if" timeline), but is finally defeated by Piccolo (with help from a confused Gotenks).
In Dragon Ball Z: Attack of the Saiyans, a side quest involves using Tien using his Evil Containment Wave to collect the 150 monsters in the game. Kami (or Mr. Popo after the battles against Nappa) gives an Offense Ring for 30 monsters captured, a Good Rice Cooker Capsule for 60 monsters, Kami's Gi for 120 monsters, and the Spark Boots Capsule for all the monsters captured. Also in Attack of the Saiyans, it is revealed that Master Mutaito developed and used the technique several years before the events of the game to seal the Evil Flame in the Divine Crossing. In the game, the demon is released by Tien while he was training at the Divine Crossing for the 23rd World Martial Arts Tournament. With help and guidance from Mutaito's spirit, Tien uses the Multi-Form technique and defeats the demon. Afterwards, Mutaito grants Tien permission to use the Evil Containment Wave and he receives a Rice Cooker Capsule which increases the technique's success rate.
In Dragon Ball Z: Dokkan Battle, the Evil Containment Wave appears as the Active Skill for Super Saiyan Trunks (Future) & Mai (Future). It also appears as a Super Attack for Master Mutaito, Master Roshi, and Shen (Possessed by Kami). In-game, Evil Containment Wave is treated as a one-time nuke that inflicts massive amount of critical damage and stun while also debuffing themselves at the same time (Roshi stuns himself and loses all his defense while Trunks and Mai halves their own defense after using the Active Skill).
The technique is mentioned in Dragon Ball Xenoverse, by Piccolo during his training of the Future Warrior. After receiving an All-Energy Capsule S he request the Warrior craft via the Item Mixture Shop, Piccolo will state that his father overestimated his powers and lost to the Evil Containment Wave, using the story as an example of how warriors shouldn't rely on power alone and should use any skills and items at their disposal to win, like how Mutaito used the Evil Containment Wave and Electric Rice Cooker to defeat and seal King Piccolo.
The technique is mentioned by Piccolo and Tien in Dragon Ball FighterZ during a special event conversation with Android 21 (Good) when teamed together during the Android 21 Arc. During the conversation, Piccolo and Tien wonder if the Good 21 is life linked to Android 21 (Evil) like Kami was to King Piccolo stating that they can use the Evil Containment Wave to defeat her evil counterpart without killing her allowing Good 21 to survive if that is the case. While she is touched that Piccolo or Tien would be willing to use the technique to ensure her survival were she life linked to her counterpart, Good 21 confirms that she and her counterpart are not life linked as their fission works like Majin Buu's due to the strong influence of Android 21's Majin cells. As a result it is decided that the technique is not necessary to defeat her evil counterpart.
In World Mission, Evil Containment Wave appears as a Giga rarity Ability. At the start of battle, if Demon King Piccolo, Piccolo Jr., Kami, or Tambourine is on enemy team, permanent -50% PWR and GRD to one of them at random. If Piccolo Jr., first change to Evil Containment Wave Reflection. Its Giga Rarity Accessory can be purchased from the Maline's Accessory Shop for 35,000 Zeni after starting Chapter 3, Sub Chapter 1 which allows it to be equipped to custom cards through Card Creation (provided their is an open Ability Slot and enough Custom Points) or equipped to any non-Special type card in a Custom Deck.
- 魔 (Ma) = Demon
- 封 (Fū) = Seal / enclose
- 波 (Ha/Ba) = Wave
- Despite the need of a containment tool to perform this technique, it was deemed acceptable in the Tournament of Power under the grounds that the container itself has no dangerous properties and because the Omni-Kings thought it was a cool technique.