So I found myself in Ninjago with team RWBY.
(For styles, picture this like the style used in monkie kid)

Me and the team were at first unsure of each other but we got along sooner or later as I made jokes with yang, I didn't care what Blake was and understood her decisions, Weiss I believed was a sweet girl only spoiled but is still a sweet and caring girl under her cold personality, ruby actually wasn't hard as when I found myself in this realm I had weapons that she drooled for and so she also helped me learn a few but I got control of them.

Later we made our way to the monastery and it was actually an agonizing climb but we soon made it.

Weiss: "Why in the name of gods did anyone place a building up here?!"

Blake sighed. "Maybe to avoid distractions?" I nodded. "Yeah, but soon it will be normal." Then I soon knocked as an elderly man I recognized answered as I spoke. "Hello sir um I don't know how to say this but... We're from other realms and need your help."

Later I explained how by some strange accident we were transported from our worlds to this one, he seemed to understand and said we could stay but we had to help keep the place clean and train just as the Ninja do, as we spoke I noticed Nya training when the doors opened showing four... Wait a minute?! Are the Ninja's girls here?! Is this an alternate universe or realm or whatever?!

Later Sensei Wu introduced us as me and team RWBY trained a bit while the ninja fought to see who would be the green ninja as I sighed knowing who it truly was, I think... Is it just them or are others also changed?

Either way me and the girls took a break to catch our breaths as I drank a tea I experimented with which actually helped my stamina and even boosted it a bit along with my speed but it was once a day use.

Suddenly Kaitlyn accidentally started a fire as I rushed over using a special Ice imbument on my own Shurikens to douse the fire a little till Sensei Wu used the golden Shurikens to put it out as I caught my Shurikens. "Thank you for keeping the fire low Felix." I nodded as he turned to the four ninja. "What were you thinking?!"

Jayden blurts out the answer. "Uh, we were trying to figure out who's the green Ninja." Zoey smacks her from behind as she tried to make it sound different but Sensei already Knows the truth. "You were not supposed to see this." Kaitlyn then spoke up. "But Sensei, we wanna know. Which one was is the chosen one?" I spoke up. "Not to be a rude guy but I don't believe any of you could be this green ninja, especially since you need to find your full potential as Sensei says." Cora got upset.

"Well it's not like you could be the green ninja, you just came here and don't even know anything about being a ninja." I just sighed. "I'm pretty sure Sensei didn't want any of you to see this because your getting an ego to be the so called "Defeater of the dark lord" plus did it say anything about Garmadon being the Dark lord as it could have said his name or title but I don't think he has been called The Dark Lord."

I then left as Weiss puts a hand to my shoulder. "Don't let her make you Upset Felix, it's like you said this whole green ninja chosen one thing is just making them smug in their egos." I smiled. "Yeah, and I know we're not ninja but we all have the same goal and that's to protect the innocent people." I smiled and she returned it as we and team RWBY went to get something to eat when Sensei cried out the serpentine were back, after telling team RWBY they also got nervous when I remembered Nya was at the village to as we joined the ninja joining in on each dragon while I got my new jetpack.

We then fly off as I wanted to have fun. "Last one there cleans the dragon dens!" I then flew off as the girls actually smiled at the challenge as I made it to the village first preparing my katana weapon.

As the others arrived I went to look for Nya as I found her hiding and the others came in shocked the serpentine are real as Nya explained the general has an anti-venom in his staff as me and team RWBY had a plan and it involved some training of ours. Ruby was giving support from the rooftops, Weiss was to block and trap reinforcements, Blake will use her semblance to distract some soldiers, and yang will have to use her other senses except sight to smash the serpentine, non-lethal to all of them. I was going to go after little Garmadon or as the Ninja called Lydia... Seriously what is with this universe?

Either way me and team RWBY head out as I chased Lydia. "Get back here little Garmadon!" As I got close I was able to use my ice crystal to freeze the ground stopping her cart. "The ninja should have taken care of you more properly, I'll handle it this time." Suddenly she cried retreat as the serpentine escaped but we got the staff as cora puts it into the fountain.

Later as the Ninja and Sensei spoke Ruby asked me a question. "So is this just the beginning?" I nodded. "Yeah Ruby this is the beginning..."

"The very beginning."