Being an old heroic mentor past his prime is never a good sign in anime, which is precisely why One Piece fans are worried about the fate of Monkey D. Garp. Death Bells recently started tolling for Luffy's eccentric grandfather after he set out to rescue his protege from Marshall D. Teach, the person responsible for the Summit War and possibly the endgame villain for the series.
Long-time manga fans have naturally begun to notice resemblances between Garp's voyage to Hachinosu Island and a similar emotional climax in Naruto, where Jiraiya reached Amegakure and was killed by the villain he had set out to destroy. Killing off old characters. As such, fans like @Geo_AW have begun to predict Garp meeting a similar fate at Blackbeard's hands as Jiraiya did after Pain's Six Paths attacked him.
Twitter predicts Garp's fate to be similar to that of Jiraiya's, possibly to incite personal conflict and raise the stakes for the protagonist in One Piece
Twitter user Geo posted a picture of the heart-wrenching scene from Naruto where fans were privy to the legendary Sannin meeting his end after being stabbed in the back. The very next picture showed the grizzled hero of the One Piece navy, Monkey D. Garp. Above that, Geo posted the caption:
Garp showing up at pirate island is hype, but for anyone who watched Naruto we all know this could end really bad
Below, he took to the comments to write that Garp sacrificing himself for Koby's sake makes sense for a number of reasons plot-wise:
Blackbeard wants to make pirate island an official government sanctioned island, he couldn’t use koby as leverage because of his sword affiliation, but I think he could use Garp
How far the fates of Jiraiya and One Piece's Garp might be similar
Jiraiya's death at the hands of Pain/Nagato made thematic sense in light of how Pain had been Jiraiya's former student. Not only did it establish Naruto and Pain as foils of each other, bringing their conflict to a personal stage, but it also signaled Naruto's growth after the death of his paternal figure. The loss of his grandfather may inspire Luffy to confront Blackbeard, who was indirectly to blame for his brother's demise.
The Shonen anime is known for heroic sendoffs for old mentor figures, and Jiraiya's demise was no different. His final battle showed fans how much power the old sage still packed and provided a grand spectacle on screen. In One Piece Chapter 1080, Garp's attack destroyed several buildings on Hachinosu Island and even showed signs that the old man possesses Conqueror's Haki.
Blackbeard himself is not here, but it is natural to feel that Oda is pulling all the stops to justify all the hype Garp has been receiving since the beginning of the series before seeing him off. As Roger, Whitebeard, and Oden are deceased, Kaido and Big Mum are missing, Sengoku and Rayleigh have retired, and the plot is now nearing its conclusion, fans' hesitations about the final epic hero from the One Piece old generation are understandable.