User blog comment:Lord Zeref Dragneel/Top 25 most powerful characters/@comment-26451407-20150812051416/@comment-1153699-20150813204706

"He was only said to have been, by Silver, as not being that strong"

...Compared to the other 9 Demon Gates. The only real thing that kept Keith on the 9 Demon Gates's level was his hax. Offense and Durability-wise, there's no doubt he was the weakest. Once you find a way to get past his hax, he's really nothing special at all. Juvia took a lot of hits from him and was able to keep fighting. Once she finally had a way to hurt him, she one-shotted him. Not to mention the fact MBP doesn't work on Demons.

So it would never be added? Even Jason's GMG stats are mentioned here on the Wiki. I don't see why Tartaros's Stats (even if they were made just for a Card Game) shouldn't be as well. They are more reliable than those GMG stats at the very least.