Headcanon on the Yu-Gi-Oh! series that may as well be canon: the first three shows (OG, GX and 5Ds) are all set in the same universe while all the preceeding shows from
Yu-Gi-Oh! 5D's Tag Force 4 - Yugipedia - Yu-Gi-Oh! wiki
5 x “Yu-Gi-Oh! World” GX/5Ds Magazines-RARE-issues #91,95,99,100+102 (P94) | eBay
Yugioh GX vs Yugioh 5d's !! - YouTube
Yu-Gi-Oh 5D's DVD Series Duel Box 5 - Solaris Japan