Fantasy Fiction Protagonist named "Shen" on a journey to become the greatest sorcerer/mage in the world, except he doesn't have magic.

[C]

I'm looking for the title of a book my husband read & fell in love with. He read it online years ago. The Protagonists name is "Shen" but he calls himself "The great Shen, God-King of the Universe and Champion of the stars." He's on a journey with a group of friends to become the greatest sorcerer/mage in the world, but he has no magic. Instead, anytime something magical happens around him, he takes credit for it. He's delusional, but harmless. My husband believes he was either half/full elf as well. Any help is appreciated!

[Tab]

How many years ago did he read this?
Was this book also available in paperback/hardcover?
Anything about the cover?
Part of a series?
What country was he in when read the book? What language?

[C]

He read the book in 2015.
He read it on his Kindle Unlimited account, which he deleted in 2016 and therefore can't see his history off.
He is unsure if the book was made to print or if it was just an eBook, but he remembers the cover was roughly hand drawn and had a lot of the color green.
He said it was the first in a series, but when he read it the other books were still being written and hadn't been released.
He read it in the U.S. and in English.