(At the Pacific Oceans, The U.S. Pacific Fleet takes Ben 10, Grimlock, Sludge, Slug, Scorn, Slash and Gwen Tennyson to investigate the water areas.)

Cpt. Dylan: We checked out this area, and there appears to be some kind of big robots flying above the oceans.

Ben 10: Are you sure?

Cpt. Dylan: (nods) Yes, our readings never go wrong. Whatever is roaming around, it's something... I don't know.

Ben 10: Well, me and my team will investigate this mystery. Hey, Slash. You want to go.

Slash: (smiles) Hell yeah, I'm completely specialized for this mission. I haven't had an aerial action ever since we teamed up with the Special Forces facing Union Academy, Asuna Yuuki and Jonathan Irons.

Gwen: (smug) Then go for it, dweeb-bot.

(Slash then knocks Gwen out, and the captain turns to Ben.)

Cpt. Dylan: Are they always like this?

Ben 10: (chuckles) Nah, it's just my cousin who tends to get on anyone's nerves.

(Then Slash and Ben 10 go outside the U.S. Fleet, and Ben 10 activates his Omnitrix.)

Ben 10: It's hero time!

(Ben 10 becomes Jetray and flies along with Slash until they hear a voice further away from them.)

????: Found you, Ben Tennyson!

Slash: (confused) Who was that? And how does whoever or whatever it is know your name?

Ben 10 (Jetray): So we meet again... Isaac Kabuto.

Isaac: Turbo Smasheeeeeer PUUUUUUUUUNCH!

(Two of Mazinkaizer's rocket punches come in and hit them, and they scream.)

(Back inside the U.S. Fleet, the others are waiting for Slash and Ben 10 to come back, suddenly they hear some screams, and see Ben and Slash crashing on the fleet. Ben 10 gets up.)

Ben 10 (Jetray): Bringing big guns as usual, I see.

Sludge: (confused) What is he talking about?

Isaac: FIRE BLASTEEEEEEEER!

(A heat blast is about to hit the fleet, but Gwen manages to shield most of the U.S. Fleet, except for three. Then they see a familiar mecha and Gwen's eyes widen at it.)

Gwen: (eyes widen) Dinobots, I guess I know what Ben was talking about.

Grimlock: (eyes widen) Is that...

Sludge: (serious) This mecha looks familiar...

Slug: Hey guys, isn't that...

Ben 10 (Jetray): Yes, Isaac Kabuto, my archrival since highschool.

Cpt. Dylan: Who is Isaac Kabuto, Mr. Tennyson?

Ben 10 (Jetray): He is the descendant of Koji Kabuto, and the current pilot of... Mazinkaiser.

Mazinkaiser: That's right, Tennyson. And we've got some score to settle.

Grimlock: (eyes widen) What score?

Ben 10: (changes to Way Big) We had some rivalry when we were kids, and it increased since I got the Omnitrix.

Scorn: Wow, and I thought Kevin was the only one.

Sludge: What is... Mazinkaiser again?

Gwen: Mazinkaiser is an upgraded form of Mazinger Z originally created as a way to compete with other super powerful robots.

Ben 10 (Way Big): Leave now. I've got this!

Cpt. Dylan: (nods) Roger. (grabs the walkie talkie) Attention all fleets, fall back to the base. We need to retreat.

(The U.S. Fleet leaves as Ben and his team prepare to fight Mazinkaiser.)

Grimlock: Okay team, let's go!

Sludge: (smirks) Oh yeah, time to fight the Demon God himself.

(Ben 10 (Way Big) Charges at Mazinkaiser, who charges back.)

Gwen: It's not a surprise that Ben makes so many enemies.

Slash: Ah, shut up!

(Mazinkaiser summons his Kaiser Blade and swings it at Ben 10 (Way Big), who blocks it.)

Grimlock: (eyes widen) BEN!

(Mazinkaiser slowly overpowers Ben 10 (Way Big) as they growl at each other, but the alien hero gains the upper hand and shoves the mecha's sword away. Then Scorn charges at Mazinkaiser.)

Mazinkaiser: Koshiryoku Beam!

Grimlock: Scorn, look out!

Scorn: (shocked) Oh no!

Ben 10 (Way Big): Damn... I'll have to take the risk.

Scorn: Ben, don't...

(Ben 10 (Way Big) shields Scorn, and then Grimlock uses his Dinobot powers.)

Grimlock: DINO CYBERTRONIAN BREATH!

(Grimlock's attack clashes with Mazinkaiser's Koshiryoku Beam, and then Gwen turns to Scorn, Sludge and Slug.)

Gwen: Beam lock formation.

Scorn/Sludge/Slug: (nod) Hai.

Gwen: MIRACLE ANODITE MAGIC BLAST!

Scorn: DINO ENERGY BOOMERANG!

Sludge: DUAL ENERGY SPEAR!

Slug: DINO SPARKLE!

(They mix their powerful attacks together, and overpower Mazinkaiser. As the dust settles, Mazinkaiser is seen standing, but somewhat damaged.)

Mazinkaiser: Round 1 goes to you and your team, Tennyson. But we'll meet again. That... is a promise.

(Mazinkaiser flies away, retreating back to Japan.)

Grimlock: Okay, let's go home.

(Then they leave and begin retreating back to Bellwood. Meanwhile, Isaac returns to his base to repair his Mazinkaiser for his next battle against the Alien Dino Thunder Force.)