So this is a pic of my Sonic Version of Palkia that I do Role play as him.
As for his personality he can be childish but mostly he is very serous for his job of controlling Space, He can be a bit of a prankster, likes to annoy his brother who is Dialga of proving who is better. For his size he is twice as big as Sonic, about the size of Big or Storm.

I had this picture for a long time on my deviantart page but i thought of sharing some of my pics here.

Palkia @ Pokemon