Yesterday (July 12), a Cameo video surfaced of Dave Mustaine, where the frontman showed a glimpse of Megadeth's "mystery bassist" for the first time. Though you can't see the musician's face in the video, Megadeth fans are speculating who it might be.

In the video, Mustaine teased fans by turning the camera on the bassist, who was lying on the floor with his arms over his head. However, in front of him was a five-string BTB Ibanez bass.

Though Mustaine confirmed that Megadeth will be revealing who the unidentified bassist is soon, fans have started coming up with theories online — and one of the leading ones says that it's Testament and Death's Steve Di Giorgio.

A user on the Megadeth Reddit posted a thread titled, "All signs point to Steve D Giorgio as the new Megadeth bassist," which featured several clues pointing to this conclusion. One image was a side-by-side of Di Giorgio holding the same Ibanez bass as shown in the Cameo video.

The second is a screenshot of a tweet in Spanish, which reads, "Tonight before I sleep I'll just say I'd love to see the great [Steve DiGiorgio] as the bass player for Megadeth," as translated by someone in the comment section of the thread. Di Giorgio replied, "Me too, son of a bitch," from his own account.

The third slide in the thread is a screenshot of Di Giorgio replying to tweets posted by the DiGiorno (ha) pizza company, "Pizza sells... but who's buying?" and "Metal is my business... and business is good."

Upon further investigation, it appears Di Giorgio tweets at the pizza brand frequently. As in, on-a-daily-basis frequently. But the Megadeth references have since been deleted from his account — perhaps to lessen the speculation?

See the images from the Reddit post below.

Another popular presumption, which is also seen in the comments for that same Reddit thread, is that the bassist is Angra's Felipe Andreoli, who also uses a similar-looking Ibanez bass. Considering his former bandmate Kiko Loureiro has also been playing guitar for Megadeth for the last few years, the close connection makes this another possible conjecture.

"The guy in the Cameo was definitely Felipe Andreoli," someone wrote in the thread.

View a photo of a five-string Ibanez BTB bass that Andreoli posted on Twitter below.

Regardless of who the bassist is, they've already re-recorded the bass parts for the new Megadeth album, which initially featured David Ellefson. Stay tuned for when the band makes the official announcement as to who it is.

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