"If evolution product of design, is evolution... evolution? Mmm... Line of thought, not productive," is a reference to the concept of intelligent design.
"An interesting old man once told me, "Stay thirsty, my friend." [pleh] Such terrible advice! [Sips his drink] Ahh!" is a reference to the Dos Equis advertising campaign The Most Interesting Man in the World.
"The Prime Evils can never be divided... except by 1 and evil," is a reference to how in mathematics, a prime number cannot have a positive divisor other than 1 and itself.
"Fear... tastes of chicken. [grumbling] Everything tastes of chicken," is a reference to the clichéd phrase "tastes like chicken."
"Let's make a deal," is a reference to the popular creative trope of making a deal with the Devil.
"By the way, did you know that the Greymane Wall is one of the few objects that can be seen from the Twisting Nether? It's true!" is a reference to the popular myth that the Great Wall of China is visible from space.
"A full moon? Tonight? No! I will turn into a monster! Hah, I jest. I can turn and tear out your throat at any time I want!" is a reference to how in most creative works werewolves only transform during a full moon.
"A crusader, a paladin and a templar walk into a tavern. And then they all have a drink. [laugh] ...no?" is a reference to typical "A priest, a rabbi, and a minister..." jokes.
"This your brain. Say hello brain. [second slightly dumber voice: Hello!] And this is your brain on fel magic. [fire effect and second voice screams] Any questions?" is a reference to This Is Your Brain on Drugs, an American anti-drug campaign.
"It's not a real space opera until the fat alien sings," (available with the Space Lord skin) is a reference to the proverb "It ain't over till the fat lady sings."
"Wait, isn't shooting a medic a war crime? Do the Geneva conventions apply in the Nexus?" is a reference to real-world international laws in the Geneva Conventions.
"Think of it, an all Shaman Expansion to World of Warcraft... We'll call it: Sham-WoW. The thing... it sells itself," is a reference to popular infomercial product ShamWow.
"Here, hold this apple for a moment... Alright, now put it on your head. Perfect. It's been quite a while since I've used this bow. [arrow sound]" is a reference to a tale about Swiss folk hero William Tell.
"[Doorbell sound] Greetings, my name is Tyrande and this is Sister Shandris. Do you have some spare time to talk about Elune? Here, take this pamphlet. [doors slam] Oh! Hello?" is a reference to Jehovah's Witnesses.
"You know, you sound awfully familiar," (when interacting with Xul) is a reference to both heroes being voiced by Michael McConnohie.
"Yes, it's precisely the kind of comment I'd expect from a troll," (when interacting with Zul'jin) is a reference to the term troll, someone (often on the Internet) who seeks to incite discord for amusement.
"If ya keep feeding to DIS troll, I'm just gonna keep comin' back," is a reference to the term troll, someone (often on the Internet) who seeks to incite discord for amusement.
"Hey! No touching da hair! I dun' grant no stinkin' wishes," is a reference to troll dolls.
The posture and the facial expression of Chromie appearing in her trailer at 1:05 is also a reference to the Disaster Girl meme.
Probius' level 20 talent, "Pobius Loop", is a reference to the geometrical shape of Mobius loop.
Some infinitely stacking quests such as Raynor's "Veteran Marksman" have a cap of 9001 stacks which is a possible reference to the "It's Over 9000!" internet meme.
Sgt. Hammer's posture, featured on a billboard on a Zerg pen on the Braxis Holdout battleground is a reference to "We Can Do It!", a famous American World War II propaganda poster.
The Special Snowflake mounts are a reference to the pop culture term "special snowflake," often used as an insult toward members of a certain generation.