INCEPTION
When Kami watched kid Goku in his final battle with King Piccolo, he had felt, in his own chest, the final hit that the young boy had delivered to the Guardian's other half. He had, in that instant, resigned himself to his impending death and found nothing but regret.
Regret for his need to separate himself, all those years ago. Regret that he hadn't been able to do more, to stem King Piccolo's Evil, after that selfish act of desperation. Regret that he had yet to locate a suitable replacement for the position of Guardian of Earth.
When the now eternally youthful, but still dying King Piccolo pushed his very soul into a new egg to succeed him, Kami had actually breathed a sigh of relief. 2 seeds had taken root in his mind at that moment. One was for Goku to succeed him as Guardian and the other, deeper, not even at a conscious level, is the cause for this very What-If.
He then took to training the boy Goku, with the hopes of moulding him into the role he has long held. But, after the 23rd World Martial Arts Tournament wrapped up, Kami's offer gets thrown back in his face. No way does the young and recently married Goku want to cast all that aside for a job. Kami has failed again, to procure his replacement.
I wonder why Chi-Chi didn't speak up then. Being married to Earth's Guardian, Effectively the god of the planet surely comes with Perks, and staff, even if it's slightly more than a normal full time position. The woman does like a working man though, doesn't she.
Once back at the lookout, Kami is considering his options when a memory comes to him. King Piccolo's son and hier, Piccolo Junior, but also his other, somewhat deformed offspring, Piano, Tambourine, Cymbal and Drum. They weren't replacements, like Piccolo. They where relatively normal children, all possessing various portion of King Piccolo's will, knowledge and power.
While Goku is off having fun and a son with his new Wife, Kami sets about his task. His first 2 children must be protectors, warriors. Fujin, a god of the raging wind, and Raijin, or Raiden if you don't mind mixing your franchises, since he's based on the Japanese god of thunder. True to their Japanese lore, they will be brothers in arms who, each having different parts of Kami's fighting knowledge and power, can and will train relentlessly with each-other.
By the time Goku is taking little Gohan to meet the Z-Fighters at Kame House, Kami has a total of 4 children. Having recovered from the excursion of producing those first 2 eggs in such quick succession, he produces 1, then after a longer break, another. Ryujin (Dragon god of the sea) and Suijin (God of Water) are, unlike their rapidly maturing siblings, both of the slow growing Dragon Clan variety.
The dynamic duo, of Wind and Thunder, are eager to meat this Goku fellow that Kami has often spoken of. So with the permission from their father, the pair take their leave of the Lookout and arrive at Kame house to the collective gasps of all gathered there.
2 Piccolos? Oh dear god no, they're multiplying!
PRELUDE-TO-THE-PRINCE
They quickly introduce themselves as Kami's children, the warrior brothers, Fujin and Raijin. Raijin, Raging? Huh, that's gotta be a pun or some sort. Goku is thoroughly impressed with what power he can feel within them and the utter lack of malice. They'll make wonderful sparing partners! However, their happy introductions are cut short when a strange man appears.
He expounds briefly about himself and Kakarot being brothers and that they, both Kakarot and the boy should come with him to meet Vegeta, their Prince.
Are we just going to ignore the fact that Raditz only brought 1 pod? A pod he can barely fit in, what with all that hair. Yes, lets do that.
Goku refuses, Krillin gets tail whipped and Gohan gets nicked. The 2, apparently, Namekians? are also put firmly in their place. This is too much, too fast. They were already a bit awkward having never before left the relative safety of the lookout. Now all of this? Wow. The world is a busy and interesting place.
When they have all recovered, Raditz is long gone, having given Kakarot a day to prove himself before meeting up and heading out... somehow all squeezing into that 1 pod. Yeah, I thought we were glossing over that minor detail.
They sense movement above them and look up to see Piccolo, who had come to watch what that odd, but terrifyingly powerful man was doing. He was absolutely NOT expecting to meet Fujin and Raijin. Who are you? How are you? Why are you?
After recapping, Goku, Fujin and Raijin ask the angry and confused looking Piccolo if he'll accompany them and pushing the discomfort aside, they all head off to face this Raditz guy.
Raditz thinks that they've changed their mind so quickly, which is great. But why bring the Nameks? They're useless weight. Kill them, Kakarot.
Goku instead tangles with Raditz alone for a bit as his Saiyan nature wants to test himself properly against this incredibly powerful opponent.
When little Gohan sees his father getting beat on, he has his requisite rage moment, busting out of the pod and barrelling into the fight. Raditz's armour is damaged, and with 2 of the 3 green men now moving toward him as well, he is suddenly feeling just a little bit in over his head.
He goes all out, managing to take Raijin out of the fight, if not actually kill him. Similar conversations occur as they continue to engage. Dragonballs are mentioned and Piccolo, seeing that Raditz's defences are just too strong, breaks out the attack he had been working on to finally beat Goku.
Having help holding down Raditz does little to save Goku's life, unfortunately. He and his brother both perish to the Makakosappo, with Goku's body vanishing to other world for Gobu to train up.
The others arrive and get to overhear the 2 Saiyans talking about coming to Earth.
Having seen some of Gohan's explosive strength, Piccolo still wants to take the boy to train him, but is stopped by Fujin and his recovering sibling. He has potential, yes, but he is just a child. You are welcome, umm, brother? to train him with us, as we prepare for the arrival of these other Saiyans.
Chi-chi is not at all pleased. Goku's dead? And you want to take her boy from her? She is mollified by the almost unnerving calm of the wind gods assurances. They will stay nearby and work carefully to make sure he is brought up to speed without too much impact on his book learning.
While Gohan's training is slightly less intense here, it is more robust, given the number of people and their less brutal training tactics. Piccolo's initial rejection of their offer does not last. They are not overly surprised when, a few weeks later he arrives, and wordlessly mucks in with them as if he'd been there the whole time.
The pair of warriors have come a long way since leaving Kami's lookout. Even in the few weeks since they last met their brother? Uncle? Having to train the new and unknown quantity of little Gohan has proven very beneficial for them both, as they re-evaluate their methods. By the time Piccolo joins them, he is lagging behind a descent amount.
Much to Piccolo's irritation, the brothers soon start to re-engage more with their father, Kami and the other Z-fighters, currently suffering away under Popo's unmentionable training. Gohan meanwhile, is getting a very well rounded martial education. He even ventures into the mystic tort.. ah, training room and meets those ancient Saiyans, along with his trio of green skinned mentors.
Piccolo is further befuddled to meet the still young Ryujin and Suijin at the lookout. They are both very much still children and are quite afraid of him, but he can't help but feel a bit of kinship with them as well. They'll certainly make nice minions some day when all these interloping Saiyans are dealt with.
SAIYAN-SAGA
When the Saiyans arrive, East City still has its worst day ever. They then head off to encounter the gathering fighters. Originally, Piccolo was at 3k5 at this time, but now, he's just below 4k, as are Fujin and Raijin, by the way, having caught Piccolo up while Gohan had his promised down time.
With the broader training, Gohan has more than made up the difference as well at around 1k2 and the Z-Fighters are all ever so slightly higher to match, having spared with at least 2 of the 3 available Namekians. Krillin is coming in at around 2k2, Tien is around 2k4 Yamcha is sitting pretty at 1k8 and Chiaotzu is bringing up the rear in the upper reaches of 800.
This overall slight improvement poses a couple of problems for the Saiyans. The Saibamen are much, much less successful. Yamcha, for one, does not get exploded, at least not to death, and the group make quick work of the remaining green abominations.
When it's Nappa's turn to play, Chiaotzu again tries to blow himself up before Tien can be killed. When the Tri-clops then one-hand Tri-beams the brute, it really hurts! In a rage, Nappa goes to make sure that the passed out Tien is dead, when Raijin steps in the way, deflecting the attack.
Now properly angered, Nappa goes all out. He is toe to toe with first 1 green teenage-looking fellow, then another. When he tries to distract by attacking the seeming weakest link, Gohan, The blast is blocked, not only by Piccolo, but by both him and Raijin. They share the blast, deflecting it away. While they both are injured and collapse, neither die.
Gohan doesn't know this though and gets a bit mad. Unfortunately his more filled out training has given him better awareness so has taken an edge off of his rage. It is slightly less powerful. On the other hand, being far more aware of himself and his surroundings, he is much less prone to locking up, you know, for a 5 year old.
Goku arrives to see Nappa being engulfed by Gohan's Masenko, but surviving. He sees Piccolo and Raijin on the ground, with the massive scorch mark in front of them and does the math.
After giving them each half of the 1 Senzu he brought with him, he takes over the fight.
Nappa is again discarded at Vegeta's feet and gets Ghost Nappad!
Goku vs Vegeta goes down mostly as you'd expect. Kaio-whatsits is yelled a lot, a Spirit Bomb is passed around, a Power ball provides Blutz waves, a couple of people go Ape and tails are eventually sliced off. While Vegeta is in his Ozaru form, Piccolo, seeing Goku getting absolutely wrecked, intervenes with his own massive form, much to the shock of his fellow warrior clan-mates.
But for one thing it hurts like a moth.. ahh, a lot, it hurts a lot, and he's just nowhere near strong enough to do much beyond distract. Raijin and Suijin are certainly taking notes though.
The spirit bomb could also be passed to either Krillin or Fujin, but the end result is likely the same. Otherwise, it's not like they have much else to do in this fight.
Goku, being Goku, asks them to spare Vegeta. Piccolo is not having it, but is stopped by Raijin, who says that this is not their way. So Vegeta escapes in his pod and heads off to get healed up.
NAMEK-BOUND
The Dragon Gang gather and take the wounded to hospital. Kami offers to summon Shenron as soon as possible, to revive Tien, but he calls down from the check-in station. They will head to King Kai's planet together, and when Chiaotzu is revived, only then Tien will come back too.
The ancient Namekian ship is introduced and the Briefs family sets to work on examining it. They don't waste as much time though as they now have not only Kami himself, but a whole cornucopia of Namekians to help them.
Who goes to Namek?
The the numerous Namekians, Bulma doesn't need to, let alone want to.
Chi-chi is shouting about not letting Gohan go, thought the boy is arguing quite coherently about how he wants to help Mr Tien and Chiaotzu come back.
Yamcha will stay right where he is, to protect Bulma.
Krillin is happy to go. His apprehension at a planet full of Piccolos has long since been quelled both by meeting Fujin and Raijin, and that time training on the Lookout, around Kami, Ryujin and Suijin.
Fujin and Raijin are or course itching to go. Kami would have certainly gone, if his duties did not hold him here on Earth, so having some of his will in them, they in turn are that much more inclined to travel there.
The children, Ryujin and Suijin, are eager as well but they're barely 3 years old at this point. Much too young to go gallivanting around the cosmos.
On hearing this, Gohan's argument collapses. Chi-Chi absolutely puts her foot down. If its too dangerous for them, it's too dangerous for her precious boy.
Piccolo, is also curious to go there though, so that could mean all 3 of Earth Warrior Namekians will end up there. But with Power levels at the low end of 4k, what good will it accomplish?
I think the ideal contingent will be the trio-de-vert, Raijin, Fujin and Piccolo, along with Krillin. Bulma gives them one of the Radars, and they board the ship.