The entire Yugioh (s0, DM, Millennium World) manga:

http://manga-access.com/manga/Y/Yu-Gi-Oh/chapter/1

Yugioh GX manga:

http://manga-access.com/manga/Y/Yu-Gi-Oh_GX/chapter/1

Yugioh 5Ds manga:

http://manga-access.com/manga/Y/Yu-Gi-Oh!_5Ds

Yugioh R:

http://manga-access.com/manga/Y/Yu-Gi-Oh!_R

Yugioh Zexal:

http://www.vizmanga.com/reader/872-yu-gi-oh-zexal-1

GO MY CHILDREN

READ THE MANGAS 

YOU MUST. IT IS YOUR DESTINY.