: Sam does not want his soul back because of the trauma it suffered in Hell. He attempts a "soul-proofing" ritual provided by Balthazar that requires the "blood of the father." Since John Winchester is dead, Sam targets Bobby Singer.
: Played by horror legend Robert Englund (Freddy Krueger), he is an old friend of John Winchester who helps Dean "die" temporarily to meet Death. Episode 11: Appointment in Samarra
: Sebastian Roché assists Sam in his attempt to remain soulless. : Sam does not want his soul back
: The reaper (played by Lindsey McKeon) accompanies Dean during his 24-hour shift. Notable Themes Supernatural Season 6 - IMDb : Sebastian Roché assists Sam in his attempt
: Despite Dean failing the 24-hour test, Death retrieves Sam's soul anyway, noting that he wants the Winchesters to continue investigating "souls" and Purgatory. He places a "mental wall" in Sam's mind to block the memories of Hell. Key Characters & Guest Stars
: Julian Richings returns in his iconic role as the Horseman.
: Dean fails the challenge after sparing a young girl's life, which causes a ripple effect of unintended deaths. This teaches him that the natural order cannot be subverted without consequences.