It wouldn't be inaccurate to call One Piece's Elbaph Arc a second version of the God Valley Incident, given the current story development. Elements such as the kidnapping of Elbaph children paralleling the Native Hunting Compeition and the presence of World Government officials on Elbaph Island suggest that the final saga might echo another God Valley Incident.
However, a key missing point in Elbaph Island might be the absence of a side that could parallel the Rocks Pirates. Fortunately, one fan-favorite group of pirates might just do the trick, and for good reason, and that group of pirates would be the Cross Guild. As one of the biggest anti-Marine agencies, the Cross Guild might need more manpower and could potentially join the Straw Hats on Elbaph.
Disclaimer: This article contains potential spoilers from the manga series and expresses the author's opinion.
One Piece: Why Cross Guild might make the Elbaph Arc the second coming of the God Valley Incident

38 years ago in the God Valley, one of the most notorious battles in One Piece history took place. The event began with the World Nobles visiting the island for their 'Native Hunting Competition,' where slaves were hunted for sport, and the Celestial Dragon who would hunt down the most could win different prizes.
During this time, some famous characters were present on the island, including Garling Figarland (the former captain of the Holy Knights). Surprisingly, the event was anticipated by the Rocks Pirates, led by Rocks D Xebec, who didn't hesitate to attack the Celestial Dragons during their game.

Fortunately, the Marine Hero, Monkey D Garp, and the Pirate King, Gol D Roger, joined forces to take care of the Rocks Pirates. Now, almost 40 years after the God Valley Incident, a similar scenario might be unfolding on One Piece's Elbaph Island, where the Straw Hat Pirates are battling the Holy Knights.
The appearance of Shamrock Figarland (paralleling the presence of Garling Figarland during the God Valley Incident) works as a great point to make these two storylines connect. However, one key missing element might be the absence of a big force like the Rocks Pirates, which had pirates who later formed their own crews.
So, what addition might the Straw Hat Pirates need, other than their current allies, the New Giant Warrior Pirates? Fortunately, the answer to this question might be the entry of a fan-favorite group to the frontlines, the Cross Guild. The Cross Guild is an anti-Marine agency formed by the Emperor Buggy and former warlords Crocodile and Dracule Mihawk.

The group has quite a big group of men under it, but it still requires an ally that would make it a Grand Line-level threat. Looking for such an ally, the Cross Guild might enter Elbaph Island in the upcoming chapters and join forces with the Straw Hat Pirates to recruit either them or the New Giant Warrior Pirates.
The addition of the Cross Guild to the Straw Hat Pirates' side would make the One Piece's Elbaph Arc the God Valley Incident 2.0. However, this time, this might go differently than before, as new pirates come with new abilities that would be a treat to watch.
Final thoughts
One Piece's Elbaph Arc is currently moderately paced, with new elements being introduced over time since the official reveal of the Holy Knights' real character designs. So, the arrival of the Cross Guild might still be far in the future. However, this doesn't rule out the chances of a frenzy on Elbaph Island, as more groups might come and make this arc one of the best ones.
Related Links
- Oda's latest One Piece interview finally explains the Cross Guild
- Next two members of One Piece's Cross Guild will only have one ex-warlord
- Cross Guild's similarities with Rocks Pirates in One Piece all but confirmed