|There is more information available on this subject at Nathan Fillion on the English Wikipedia.|
- "I'm a Halo guy. The Bungie folks were kind enough to have me do a voice for Halo 3. So there's nothing like sitting down to a nice game of Halo and shooting at myself. I like to get online, and the reason I like it is I've got a lot of friends in Canada and New York, all over Los Angeles and at great distances. Sometimes I take off for months at a time to go work, and my social time is on that box. You put on a little headset and unwind with your friends. You hang out, you laugh, it's good times. And when it's all done, you don't have to send anybody home. No one's drunk all your beer. You just say, "good night, I'm going to bed", and it's off and it's done."
- — Nathan Fillion on Halo
In Halo 3, he supplies the voice of Gunnery Sergeant Reynolds, named in homage to Fillion's most famous character. Not only does Nathan Fillion provide the voice for Gunnery Sergeant Edward Buck in Halo 3: ODST, but the character's physical appearance was modeled after the actor as well. Fillion has also confirmed his work as a voice actor in Halo: Reach reprising his role as Buck for a cameo in the level New Alexandria, and also providing the character's Firefight voice. Fillion once again reprised his role as Buck in Halo 5: Guardians.
- Nathan Fillion and Tricia Helfer (the voice of Captain Veronica Dare) recorded most of their voice work for Halo 3: ODST in the same recording booth, which is rare in voice acting.
- Throughout the campaign and in Firefight his character Buck can repeatedly be heard saying "'Bam!' said the lady", a piece of slang used to emphasize conclusiveness that Fillion thought up and is trying to promote. The phrase can also be heard on Fillion's detective show Castle. "Bam, said the lady," is also the final sentence of the novella Halo: New Blood, which presented from Buck's perspective.
- Fillion was nominated in the category "Best Performance by a Human Male" for his role as Sergeant Edward Buck in Halo: Reach at the 2010 Spike Video Game Awards.
- Fillon claims to have invented the radar jammer, for which he was given the previously Bungie-exclusive Bungie Armor permutation in Halo 3.
- Nathan Fillion references his role as Gunnery Sergeant Reynolds during the song "Better (Than Neil)" from Commentary: The Musical, the side-feature commentary track from Dr. Horrible's Sing-Along Blog.
Nathan Fillion with an SRS99D-S2 AM Sniper Rifle replica.
- Comic Book Resources: Nathon Fillion talks about playing Steve Trevor in "Wonder Woman"
- Hawty McBloggy - Nathan Fillion's Halo Dreams Will Never Come True
- Halo 3: ODST interview with Brian Jerrard
- Halo: Reach, level New Alexandria
- Game Informer, July 2015 issue
- NeoGAF - Frank O'Connor confirmation
- IGN Video: Halo 3: ODST Xbox 360 Behind the Scenes - PAX 09: Nathan Fillion, Tricia Helfer and More (Off-Screen)
- Bungie Podcast: The Bungie Day Podcast; hosted by Luke Smith, Brian Jarrard, Eric Osborne, Martin O'Donnell, Joseph Staten along with Nathan Fillion