The Return of Bardock

Goku's death?

Goten senses that Trunks is in trouble as he flies as fast as he can to help him but by the time he gets there, he finds Trunks laying on the floor, almost dead. 

Goten: TRUNKS! WAKE UP TRUNKS PLEASE LISTEN TO ME! Damn you!

Tuffle: Don't even bother waking him up, he's been long dead, along with his sister.

Goten: Bulla! No!!

Goten calls on Gohan for help, then all of the Z fighters, and finally Goku and Vegeta.

This tuffle has found out about Gine's ship, tracked it down, and decided to take revenge on all of the saiyans. He ends up almost killing Trunks, Bulla, android 18, android 17, Gohan and pretty much defeats all the Z fighters. Vegeta then comes in, and is able to conflict some damage, especially after raging over bulla and pulling a  "THAT'S MY BULLA!!!!!"

Vegeta inflicts way more damage on this Tuffle, who goes by the name of Sandara than Goku, but he loses in the end due to the fact that the tuffle is able to destroy his enemy, using an attack called the shaco-gun, which shoots out a grey blast, which instantly knocks out the enemy, leaving them lifeless for a long period of time. Even Goku in his ultra instinct form, could not land a punch on Sandara. 

Sandara: You may be fast, but you cannot dodge the shaco-gun. The shaco-gun will freeze you before you receive the blast, so that you immediately die.

During all of this, Goku runs away and lets the other Z fighters hold him off until he collects enough energy for the spirit bomb.

Gine feels extremely guilty as she thinks it is partly her fault for escaping and now, after destroying the earth, this man will probably track down the hidden planet and possibly hurt Bardock

Goku collects enough energy for the spirit bomb and as he is ready to throw it, he tries to push away Sandara's attack and fails, so he keeps pushing his spirit bomb against the shaco-gun

Gine: At this rate Kakarot will die! Because of me! 

Bulma: Don't say that Gine! Goku always finds a way to--oh no

The shacogun easily beats Goku's spirit bomb and Goku almost falls to the ground from a high distance in between two bridges, but an unknown saiyan saves his life. However, the others do not know that as they cannot see, so they just assume Goku died. Gine cries and keeps blaming herself while Bulma cries for her children Bulla, Trunks, and her beloved Vegeta.

As the mysterious saiyan carries Goku, he goes underground to have a conversation with him.

Goku opens his eyes and says, "Whh-who are you?" 

The unnamed saiyan smiles and says," A long time ago, I sent my son kakarot to Earth"

Goku: Then that means y-you are--

Bardock: it's finally nice to meet you kakarot. You really became a super saiyan, you even beat Frieza! Now you must break your limits and unleash your power!

Goku: It's useless, I've tried everything! I just can't do it on my own!

Bardock: Who said you're alone? 

Bardock puts his hand on Goku's shoulder and gives Goku a boost of energy

Bardock: Kakarot, hurry up before he freezes you and kills you with the shacogun! Use your ultra instinct to distract him and be quick and I will land the final blow since he does not know that I am here got it?

Goku: Yeah!

Bardock: Make sure to get out of the way using instant transmission kakarot!

Goku: I'm ready

Goku and Bardock team up, and the father and son bond does not fail, Bardock, using all of his power blasts Sandara with an even stronger attack than the shaco-gun, called the RARENAI HA! The attack means, "The Unstoppable" in english since it can go through anything and never stop.