In issue #8 Jill is about to fly on a plane but Death from the Basanos appears. Her reaction is to to say "Im not gonna fly with you as a partner".
After that Death tells her that they need her to do something, when she asks what, his answer is a very deadpan "Guess"
Nearly any scene with Gaudium, but especially the one-off issue in which he and fellow Deadpan Snarker sibling Spera go on a quest. Also, if mainly in that context:
"He told us to think for ourselves, right? So how did that lead to us storming heaven in "I Love Lucifer" t-shirts?",
"If I'd had eyes back then, I'd have been staring moodily into his, 'stead of bobbing up and down like a cheap special effect."
"You know cherubs are spherical because it's the perfect platonic shape, right?"
"Oh good, I thought she'd put your eyes out with those things."
"I'm gonna sue this guy's ass into geostationary orbit."
"Oh, and someone set the bathroom on fire."
On hearing a hare-brained scheme of Gaudium's, Spera's reaction is a dumbfounded, "I open my mouth to speak. Nothing comes out."
And this marvelous exchange:
Gaudium: Hey! How come it's snowing?
Spera: This isn't snow. It's ash.
Gaudium: Okay, then let me rephrase the question. Why is it ashing?
Lucifer himself gets a few in, notably (early on, to Amenadiel): "I'm sure they'll explain it to you one day. Some big, hairy archangel will sit you on his lap and give you the talk."
Also, Mona and Elaine being invested as tutelary spirits, in charge of (respectively) hedgehogs and "everything except hedgehogs". While drunk she admits some anger at the hedgehogs as take advantage of her, taking great risks knowing that she'll be there to save them
Incidentally, Elaine's request gives us possibly the only moment when Lucifer seems at a loss for words out of sheer astonishment, with a beat panel of wide-eyed silence.
When Amenadiel empties a glass of brandy onto a table and sets fire to it to make a point, Lucifer comments that if he had known the angel was going to waste it on melodrama he would have given him a poorer vintage.
The entire The Yahweh Dance Issue.
Elaine blows up her first few worlds by accident, Lucifer mocking her all the while.
Her hasty, rather clumsy physical interactions with her world being interpreted as a great signs from an all knowing deity. And they start killing each other over their interpretations of said acts.
She eventually manifests in full deity, telling them to stop being so stupid in person. Lucifer is not impressed.
On his arrival in Jotunheim, Lucifer is met by two gigantic guards. The first Jotun unleashes a string of insults and threats; before Lucifer has time to react, the second Jotun clubs the first one to death.
Jotun: I hope you'll bear no grudge over the words of a fool.
Lucifer: A grudge? Not at all. I'm impressed. If you're always so quick to weed stupidity out of the gene pool, it's easier to understand how Loki happened.
At one point, Elaine says "Oh, thank God!" Lucifer's response: "Thank who?"
In the new series, Lucifer and Gabriel are in the Dreaming, which is of course filled with memes from the collective consciousness of humanity. They encounter a Big Red Devil claiming to be Lucifer.
