Arrow Season 5 Finale: Ranking The Probability Of 17 Major Character Deaths In 'Lian Yu'
7. John Diggle
This is one of the most tragic routes the show could go down, given how great a presence Diggle has been on the show since its very beginning. While he has at times been pushed too far out of the fold, Dig has remained the solid foundation of Team Arrow upon which Oliver relies, and losing him in the finale would be a major blow. It'd also leave his child without a father, and mean Lyla losing her husband.
If there's a death that would truly, as Mericile says, leave Oliver reeling, then Diggle's would certainly be that and then some. We've seen Diggle over the years go from bodyguard to fully-fledged vigilante, and having emotional character arcs with Lyla, Oliver and Andy. In short, there might not be many new directions to take the character. Oliver lost his best friend in the Season 1 finale, and Season 5, with its theme of legacy, could repeat that.
At the same time, it's almost impossible to imagine the show without John Diggle, and it's be a very bold move, but it seems more plausible now than ever before.