Variety
A squinty-eyed, cigarillo-chomping gunslinger of nebulous motives played by an actor with the last name Eastwood. An abducted woman. A few bloody shootouts. Some lovely footage of the American frontier, as played by a foreign country. On the surface, “Diablo” would seem to have all of the proper ingredients for a rollicking retro Western, yet its sights are set a bit higher, which inspires both admiration for its moxie and disappointment that its script and direction aren’t up to the challenge.
Blizzard Entertainment has filed a new trademark related to Diablo, that suggests Diablo's previously suggested Netflix series might be on its way.
AVClub: Seeing as the Western is going through a small but notable revival, it’s only logical that some total swill should come along, lest anyone get to thinking that the genre only ever produced interesting movies. And so, in rides Lawrence Roeck’s inane Diablo, boasting photogenic Canadian locations and a script that could pass for Donald Kaufman-esque parody. Casting Scott Eastwood—this generation’s answer to Chris Mitchum—as a Civil War veteran haunted by past misdeeds, Roeck aims for an homage to Eastwood Sr.’s revisionist Westerns (think The Outlaw Josey Wales, Unforgiven, etc.), but the result is pretentious and pointless. Directed to resemble rather than act, Eastwood comes across as stiff and unemotive, though Diablo doesn’t even have the sense to let its star get upstaged by the overqualified supporting cast, presumably because they would distract the audience from thinking about how he looks kind of like his father from certain angles.
FGE - Diablo is neither good nor bad, but it’s absolutely gorgeous. Scott Eastwood’s (the son of Clint Eastwood) first Western is as rocky and uneven as the terrain his protagonist ventures upon.
