The Elemental Hero in Teyvat - Boboiboy x Genshin impact Crossover

Prologue

In planet Quabaq

Boboiboy, Gopal, Adudu, Papa Zola, and his daughter Pipi Zola are staying on planet Quabaq. They are hiding from Retak'ka, an enemy who is the owner of the first elements but he stole those elements from different people

Boboiboy, Gopal, Adudu are training under Hang Kasa. BoBoiBoy's and Gopal's final test of sparring against Hang Kasa, BoBoiBoy splits up and starts attacking Hang Kasa. Hang Kasa tried to hide admitting that he has become fast. Gopal uses Cookie Crumble Transformation on his staff, helping BoBoiBoy to get the crystal. BoBoiBoy then manages to catch it with his Earth Golem.

However, BoBoiBoy and Gopal were said to pay training fees, at which Gopal only has one dollar. They suddenly spot a worried Papa Zola below them. Hang Kasa mentions another way to pay for their training by means of taking BoBoiBoy's Quake Element. He trapped BoBoiBoy and Gopal in Crystal, and in no time he start absorbing the Quake Element.

After Hang Kasa has taken the element BoBoiBoy asks why he does that. At the same time Papa, Pipi, Adu Du, and Probe showed up and asks Hang Kasa why he lied to them. Pipi reveals that in the basement they discovered Ochobot, who was used to power all the machines in Kasa's house. They also found out that Hang Kasa was the original master of the 3rd level of the Earth element after Quake, Crystal. It suddenly then turns out that Hang Kasa actually fixed Ochobot's databank; revealing that Koko Ci had actually told them to go to Planet Quabaq and find Hang Kasa and fight him to find a way to defeat Retak'ka. Hang Kasa then start telling them the story of him and Retak'ka. He said that Retak'ka was thrown out by his parents on Planet Gugura, a large garbage dump; where he finds Hang Kasa. They soon become best friends. They discovered two Power Spheres CrystalBot and GammaBot.

Together they become unbeatable in battles. However, Retak'ka became greedy, for him this was not enough. He killed other elemental power owners and gaining their powers. Finally, Retak'ka turned against Hang Kasa for his Crystal power. Hang Kasa managed to defeat him and froze him in a crystal prison and used Ochobot to take away his powers from him.

After this story, ButlerBot came running and tells that he had received a message from Retak'ka, who still found him cunning and deceptive. Tok Kasa had sent the location of BoBoiBoy to him in an attempt to bait and trap Retak'ka. Retak'ka tells BoBoiBoy to meet on Earth, saying that if he hadn't come he will kill Fang, Yaya, and Ying. Kasa also realizes that the Crystal Prison had kept him younger than he normally should be.

Hang Kasa teleports to Earth to look for Retak'ka, whom he mentions to Retak'ka that he has a stomach ache in an attempt to double cross Retak'ka. But Retak'ka instead attacks him saying that "do you think that I will not recognize you Hang Kasa?!"

On the other side, BoBoiBoy suddenly remembers Fang, Yaya and Ying, who were held as hostages in Retak'ka's spaceship

Meanwhile, Hang Kasa activates CrystalBot, then uses Crystal Shield to block Retak'ka's Thunder Blade. Pipi hesitates to activate EggaBot cause she wants to wait for it to be fully charged, but Papa Zola said him to hurry. Pipi turns into Hardshell Tortoise prematurely to free Gopal and BoBoiBoy. Retak'ka then overpowers Tok Kasa as thanks for crystallizing him, before breaking Kasa's Crystal Armor is his Tempest form. Retak'ka announces his intention to kill Hang Kasa, but BoBoiBoy blocks the attack as Blaze. BoBoiBoy then transforms into Ice to distract him with Ice Bow. Retak'ka retaliates by pinning him onto a rock and strapping him with vines as Darkwood. Ochobot then feels that BoBoiBoy is in danger, but Gopal say that they can't let Retak'ka see them there.

On the other hand, the Zolas proceed to free Fang, Yaya, and Ying, only for the Miners to spot them. Pipi Zola tells them that they are going to the market, not before the Adu Du and Probe save Papa Zola from being hit with a pickaxe. Enamored with Ayu Yu, Adu Du attacks the miners just because they corrupted her. While trying to free Yaya, Pipi is knocked off EggaBot, while Adu Du continues to fight for Ayu Yu. Adu Du proposes his love to Ayu Yu, only for him to be smacked in the head with a crystal rod. Retak'ka prepares a wooden hammer to smash BoBoiBoy, but Tok Kasa interferes and blocks the attack. Tok Kasa insists on giving BoBoiBoy the Quake Elemental to encourage BoBoiBoy to stop Retak'ka and apologizes BoBoiBoy for giving him a betrayal. However, BoBoiBoy complains that he has only two Elements left before Retak'ka continues smashing Tok Kasa. Boboiboy shocked and felt guilty that he can't help but Hang Kasa said the last words. He explained about using one element wasn't enough but he explained that the elements can be combined if he uses two of them