We learned not to mess with Aubrey Plaza:

OuchWhatDoYouDo: To me your character is honestly the funniest on the show. Being so deadpan, how often do you crack or cause others to crack while delivering lines? I’d like to see you and Aubrey face off in a “who can get the other to smile first” contest.
Nick Offerman: I will never defeat Aubrey in any contest, because, quite simply, she employs black magicks in her combat, which some would call unfair or “morally bankrupt”, but I would never cast such a aspersion, for fear of her macabre retribution. Aubrey is kin to the Black Goat Mother of a Thousand Young, yea, she has known the spoor of Shub-Niggurath, and upon the black midnight of her birth, every blossom of the pretty little Gilly flowers perished all across Trafalgar Square. Up jumped the Devil, and off they crept. In short, she is League with Lucifer, but I really respect her work.

[Editorial Note: yes, he made a Lovecraft reference. Did you know Nick Offerman "was super into 'Call of Cthulhu' LARPing in college"?]

[Photoshop based on "Cthulhu's Approval" by hwango.]

We learned about his other castmates as well:

cutiepatootieadipose: How hard is it to keep such a straight face when filming Parks and Rec?
Nick Offerman: It is very hard to keep a straight face because my castmates are literally the funniest collection of people working today. Amy and Pratt and Aubrey and Aziz and Adam and Rob and Rashida and Retta. Every single cast member. Devastatingly funny.
CubbyRed: Poor, poor Jerry.

retinarow: What’s your favorite thing about each of the cast members of Parks and Rec?
Do you worry that you’re going to be defined by this role for some time?
Nick Offerman: Amy – Her ability to combine mischief with leadership and generosity of spirit.
Adam – His sweet, gumdrop caboose.
Pratt – Best personality ever, like a golden lab meets Don Knotts. Also a fine backside.
Rashida – Incredibly well-adjusted and lovely for having been bitten by Michael Jackson’s monkey as a child. Not a euphemism.
Aziz – He can say anything in the most hilarious way – also keepin’ them buns tight.
Aubrey – She is beautiful and wonderful – not evil, don’t be ridiculous.
Rob – A champion in every way, super funny – wouldn’t mind a tad more junk in his trunk.
Retta – Could rule the world if she so chose. DISCERNING. Beautiful.
As far as typecasting, I honestly don’t really give a shit. I feel pretty damn lucky to have landed in the role of Ron, and if I am defined that way, well, I can think of worse problems. If no one will hire me after Ron then I’ll have to suffer through making things in my shop, performing live theater, and paddling my canoe with my wife. Yes, that was a euphemism.
sew3: Of course he leaves out Jerry.

We learned about a Parks and Recreation pitch that needs to happen:

Rossymagic: There’s a person here in the UK who represents manliness, stoicism and simple pleasures. His name is Des Lynham. After using devious means to watch P&R I came to the conclusion that both you and he should put your heads together to make a collection of manly fragrances.
Cut Grass, Woodsmoke, Black Coffee and Garden Shed would all give the florid notes of Givenchy, Channel and CK the fear of god
Nick Offerman: Funny, I pitched a story to Parks and Rec in which Ron turned out to be old pals with fragrance king Dennis Feinstein (Dante Fiero), played by my hilarious pal, Jason Mantzoukas, and my fave part was pitching fragrances like Gravel, Tool Steel, Flank, etc. I won’t list my best couple, in case it becomes an episode some day…No Spoilers!

We learned more about Amy Poehler’s awesomeness:

wheredidjp: How much of Parks and Recreation is improvised? When did you first meet Amy Poehler, and how awesome is she in real life? Also, sharing this awesome photograph. A friend spotted this and took a photo while walking around the Coachella 2012 campgrounds (this was taken on the first morning of the second weekend of the festival; we were just a few cars away from this camp)!

Nick Offerman: Too many questions. That looks like a fine camp at Coachella, one in which I would like to consume intoxicants. A small portion of P&R is improvised, although we have a lot freedom to spout off as we see fit. The thing is, the writing is so sublime, there is seldom any need to improve upon it. We do love to play, so we always start having extra improv fun in the later takes. I met Amy in the early 90′s and she is like a superhero mixed with both Coach and Tammie Taylor from FNL, as well as Tim Riggins and a little Landry.

We learned about Chicago in the mid ’90s:

FkYouFlipFlops: Living in Chicago in the mid-90s; did you ever feel like joining the ever-popular improv scene?
Nick Offerman: No, I did not. The comedy world and the “straight theatre” were very self-contained, very autonomous groups, and I was in 100% ignorance to that fecund chuckle-field. I was working on plays, mostly with my company, The Defiant Theatre, 24/7, so it was all I could do to see another play that a friend was in, let alone go see comedy.

[Editorial Note: Had to include this for the use of "fecund chuckle-field" alone.]

We learned what action refers to:

M374llic4: How much action does your mustache see? Is it more than you actually see yourself?
Nick Offerman: If by “action”, you mean “the puss”, I’d say that is not for public consumption, either literally or figuratively. The rumors that my moustache has a burgeoning career in Japanese porn are almost entirely unfounded. As far as I know.