Hang on. No it's definitely Tama.
There are many clues, but I won't spoil them. Once you open your eyes properly and read the chapter. You'll see.
First of all, erase Gum Gum from your mind. That was a red herring from Who's Who and discarded almost immediately. The real focus was Nika.
Second of all, focus on the chapter itself. The Gorosei have referenced a mysterious devil fruit in two chapters.
The first chapter: it ended with Zunesha.
The second chapter: It started with Zunesha.
Now, people have said it is Tama. And I'm one of them.
Use your brain: Where did Marco spend 5 chapters running? To Otama's side. Now why would he do that?
Speaking of Tama, where does her scene in this chapter come. Right after CP0, the others are snippets.
Now, what do CPO say: From Luffy, when they move to the mystery thing, they say; "This group."
In other words, the mystery thing has nothing to do with Luffy at all but with this group. Like, when you get familiar with Oda's style, you can read it.