Excalibur
Hint 1: It's in the badly drawn frame. All of them are bad? Oh right.
Hint 2: "Whoso pulleth out this sword of this stone and anvil, is rightwise king born of all England."
Hint 3: It's part of the first frame.
"Me smash you die!" is also a reference to ogre shouts in World of Warcraft.
Aperture (Portal)
Hint 1: "Cake, and grief counseling, will be available at the conclusion of the test."
Hint 2: "There should be a portal device on that podium over there. I can't see it though. Maybe it fell off. Do you want to go and have a quick look?"
Hint 3: It's part of the fourth frame.
Avatar (TLA)
Hint 1: "Water... Earth... Fire... Air"
Hint 2: "MY CABBAGES!"
Hint 3: It's part of the third frame.
Han Solo, Chewbacca
Hint 1: A handsome smuggler and his hairy friend.
Hint 2: "Yes, Greedo. I was just going to see your boss. Tell Jabba I've got his money."
Hint 3: It's part of the first frame.
Tweety
Hint 1: A little bird told me this one isn't too difficult to find.
Hint 2: "I tawt I taw a putty tat!"
Hint 3: It's part of the last frame.
Kermit the Frog
Hint 1: "It's time to play the music! It's time to lime the lights!"
Hint 2: "It's not easy being green."
Hint 3: It's part of the sixth frame.
Shingeki No Kyojin
Hint 1: This one is obvious, but if you haven't seen the show you probably don't know her.
Hint 2: She's part of the fourth, eight and ninth frame.
Hint 3: It's a version of Sasha Blouse from Shingeki no Kyojin (Attack on Titan).
Dr. Who
Hint 1: "Hello, I'm the Doctor. Happy Easter!"
Hint 2: "Exterminate! Exterminate! Exterminate!"
Hint 3: It's part of the second frame.
Where's Wally/Waldo
Hint 1: Where is he? Did you find him yet?
Hint 2: Red and white stripes.
Hint 3: It's part of the tenth frame.
Pokemon
Hint 1: "Gotta catch em all!"
Hint 2: "A caterpie may change into a butterfree, but the heart that beats inside remains the same" - Brock (It's a minor hint, but a great quote.)
Hint 3: It's part of the seventh frame.