Yay! A rubber champion! Good to a see a Mr. Fantastic / Luffy character idea around here.
I've gone over it a bit, and here's what I've got:
No real comment on the Lore I'm afraid. I'm not much of a writer or story analyst or anything like that. Looks good from here though!
Passive looks good, thumbs up! Although small clarification: does it trigger on every third ability, or do you have to use the same ability three times in a row?
Clap looks good.
Pull n' Throw is awesome, although perhaps too awesome. The ability to move champions (especially enemy champions) around quickly is really good. What I'm actually concerned about is how it's used. It looks really clunky since you have to click once to pick them up and then again to push or pull them. What happens if you wait too long before deciding? Perhaps it would be easiest if you could only push normally, and then if used with his passive you could pull. His arms stretch further and further out ... until they can stretch no more. They rapidly retract, bringing whatever they have grabbed along with them. 
Duck n' Cover is hilarious. It's probably fine, although I'm not quite sure how it works since it's so weird. 
I mean, what happens if he gets stunned?
Everything looks okay on the Ultimate, although I'd prefer something a little less similar to Pantheon's. That's not a balance thing though, just a personal preference.
Overall I like it, just think it needs a little cleanup. Oh, and I can't really help with number balancing. I'm totally lost there. 