Given Disney and Lucasfilm's professed safeguards on information leaks about Star Wars projects such as The Mandalorian, you just know the companies are letting drips of news out through unofficial channels to get us all enthusiastic about the show's return. The latest piece of casting news for Season 2 certainly has that effect: Deadwood/Justified's Timothy Olyphant will appear.
In what capacity we don't yet know, but we sorely hope that he'll get to raise a blaster (or two) in his time on the show, given his history with weapons. Since Season 2 wrapped shooting before the big Coronavirus shutdown, he'll already have completed his work alongside some other new arrivals to the series.
So far, we've learned (though Jon Favreau, Dave Filoni and co are keeping typically quiet) that Rosario Dawson is playing animated favourite Ahsoka Tano, and Katee Sackhoff is Bo-Katan Kryze. Michael Biehn will be an unspecified character, while Temuera Morrison will return to the galaxy far, far away (and Boba Fett's suit, though it's still unclear whether it's Fett having escaped from Return Of The Jedi's Sarlacc or someone else in the gear).
With post-production chugging along via remote working, The Mandalorian is still scheduled to land on Disney+ in October. As for Olyphant, he'll pop up in Season 4 of Fargo and has a role in Theodore Melfi's film The Starling.
UPDATE: According to Slash Film's sources, Olyphant will be Cobb Vanth, a character introduced in Chuck Wendig’s Aftermath book series. Vanth is the self-appointed sheriff of the Tatooine-based settlement Freetown, in which he wears a mysterious set of Mandalorian armor that was acquired from Jawas who scavenged the wreckage of Jabba the Hutt’s sail barge shortly after the events of Return Of The Jedi.