One of the most important additions in the new timeline is the mysterious collection of Infinity Items. I was tinkering with the idea of other magical item sets as far back as the middle of the road timeline, in Der Engel des Todes. There, I was going to have Viking items. I believe they were called Eon Items? In the new timeline, a Viking spear is a vital component of the story White is in the Winter Night and is called the Eon Spear.
The origin of the Infinity Items lies with my desire to find a way to save Yami Bakura. I had long felt betrayed with the revelation that Yami Bakura was both Zorc and Thief King Bakura, as he had always been Thief King Bakura to me, and honestly, well, I just loved him so much and wanted to believe he could be saved that it was a horrible blow to think of the personification of the darkness in people's hearts being part of him. I stewed for several years over the problem and whether Thief King had been destroyed along with Zorc. I hated that thought too.
Finally I came up with the concept that Thief King was still around, and that Zorc's destruction had caused them to forcefully separate. Thief King would go back to Bakura, perhaps unconsciously, seeking some kind of help and believing his spirit was being destroyed. But since I also didn't want him to have to go back to possessing Bakura, and his spirit was seriously damaged from the separation from Zorc, I slowly put together the thought of a magical item that would grant him physical form. He could only use it if he would pledge to use it for good, and someday he would be required to use it in a dangerous battle between good and evil. I had Shadi deliver this item, and with him was my old angel character Kasumi (although not identified by name). This idea wove itself into The Pendulum Swings, which was the first YGO story I'd written in a while up to that point and, I felt, was what kicked off the new timeline. Everything hinged on that venture, which heavily shaped the rest of my new YGO world.
As the adventures deepened and Thief King Bakura (still called Yami Bakura for identification and because that was how I always thought of him) tried to find out what his Infinity Item could really do, it was inevitable that he would encounter others. In the very dark yet very vital to the timeline story White is in the Winter Night, the Infinity Star is introduced. It is being worn by a serial killer known as the White Death, albeit he doesn't actually call on its powers for anything other than sustaining his life. When he finally does use the Star for directly evil purposes, it turns against him, incinerates his body, and vanishes. It hasn't been seen since, but presumably it returned to wherever these items are stored.
Dragons at Dawn revealed the Infinity Ankh, held by Shadi, which can repair fatal damage to a mortal body if it was not the person's time to die and Shadi has permission to bring them back. The following story, An Eye for an Eye, has made mention of the Infinity Puzzle, which Shadi gives to Atem. Its full powers are not yet known, but it can cast protective barriers. Unlike the Millennium Puzzle, which was upsidedown as a symbol of the dark magic that formed it, the Infinity Puzzle is right-side up.
While the Millennium Items are gold, the Infinity Items are silver. Mainly that was because I was trying to keep them different. A couple of times, however, I unconsciously slipped and wrote or drew them as gold. I need to fix that....
Shadi has revealed that the Infinity Items are powered by white magic. He seems to be one of those charged with looking after them as a whole, but he has indicated that he is not the one with the final say. He was not in favor of giving the Ring to Yami Bakura, but those higher up insisted.
There are other Infinity Items out there, but exactly what they are, what they do, and who has them is not yet known.