Wizard and Glass provides examples of the following tropes:
All Girls Want Bad Boys: Bad boys want bad girls, as well. Coral Thorin and Eldred Jonas shack up. They each state that the other is the best lay they've ever had.
Being Watched: Rhea, and others, are able to do this through Maerlyn's Rainbow.
Black Comedy: A joke about a literal dead baby is vital to the plot.
Click Hello: The first confrontation between the gunslingers and the Big Coffin Hunters features a chain of one after another.
Coitus Uninterruptus: Jonas and Coral are having sex when they hear the oil patch getting blown up by Roland's team. They don't stop, because they "had reached the point where it was impossible to stop, even under threat of death or dismemberment."
The Gunslinger: Roland of course, but in this book we see other gunslingers, and failed gunslingers.
Hate at First Sight: Rhea hates the young and beautiful Susan when she's called up on to examine her purity because she's young and beautiful, which eventually becomes a huge snarled mess resulting in Susan's death at the end and the implied death of Rhea via revenge on Roland's part.
Rhea. She basically orchestrates a majority of the events in the book, including Susan's demise Then she causes Roland to to shoot his own mother by accident and manages to get away scott-free.
Clay Reynolds survives the events of the story, but the narration lets us know that he was killed shortly thereafter in an unrelated shootout.
Kill 'em All: Even the characters who survive in Roland's story are dead by the time he tells it, except for Sheemie.
Logic Bomb: Faced with an insane but brilliant A.I. that has challenged them to a riddle contest, Eddie forces it to guess the punchlines of bad jokes. It guesses them correctly, but doing so causes it great strain. Under a barrage of them, each more illogical than the last, Blaine finally short-circuits.
"Why did the dead baby cross the road? Cause it was strapped to the chicken."
The Man Behind the Curtain: a theme of the entire series, but this book explicitly discusses the concept.
Mexican Standoff: What could be the most over-the-top straight version ever. Depape holds Sheemie hostage, Cuthbert gets the drop on him with a slingshot, Jonas sneaks up on Cuthbert and puts a knife to his throat, and Roland gets behind Jonas with a knife to his back.
Roland, at least relative to Eddie, who cracks too many dead baby jokes.
Blaine can guess the punchlines of jokes, but he hates the illogical nature of them, to the point that they can become a Logic Bomb.
OOC Is Serious Business: Cuthbert. If he's not smiling or joking around, expect serious shit to go down.
Red Right Hand: Eldred Jonas has white hair, a limp and a quavery voice, all of which are apparently the result of the traumatic beating he received when he failed his trial to become a gunslinger. His failure is probably the reason why he's such a scumbag.
Shout Out: The climax directly recreates the climax of The Wizard of Oz.
Stout Strength: The bouncer at the Mejis bar has an enourmous belly.
Sudden Sequel Death Syndrome: Tick-Tock Man gets saved by Richard Fannin(or Randall Flagg?) only to have him intentionally die almost immediately by the hands of the ka-tet.
Traumatic Haircut: Rhea hypnotizes Susan and orders her to cut off her hair after losing her virginity. However, when she tries it, Roland stops her.
The Western: "Is it a Western?" "All Roland's stories are Westerns."
What Happened to the Mouse?: At the end of the flashback, Roland's mother gives him a belt. He promises to tell his ka-tet the story of how he lost the belt, "for it bears on my quest for the Tower." Whether he tells the ka-tet or not, he never tells the reader; the belt is never mentioned again either in the main series or in any of the side materials.
Your Mom: Eddie to Blaine: "Sticks and stones may break my bones, but words will never hurt me. Or, as we used to say back in the neighborhood, 'You can rank me to the dogs and back, but I'll never lose the hard-on I use to fuck your mother.'"
Roland to Blaine: "I cannot even say you fucked your mother, for you had none."