Song: Jump by Van Halen from 1984, 1984
In Wade's hideout there's a Nintendo lunchbox (haven't managed to catch the game)
There's also a crushed Carl's Jr cup
There's a bunch of stickers near these but I've only made out the GSS sticker so far
Entering the Oasis, we first see Minecraft World after the long shot of a bunch of worlds
Uncle Henry and Auntie Em's house from The Wizard of Oz, 1939, directed by Victor Flemming, is flying around in Hurricane Hang Gliding
Batman, from the 1989 movie of the same name, directed by Tim Burton, seen climbing on Mount Everest
Planet Ludis flashes by, a reference from the book which is otherwise almost completely absent from the movie
Wolfman, The Wolfman, 2010. I say this version because of what he's wearing
A girl in a white and (grey? blue?) striped dress changes into The Flash, DC Comics
Ray Harryhausen Cyclops from the 7th Voyage of Sinbad, 1958, directed by Nathan H. Juran
Borg? (off to the left of the cyclops)
BattleToads?
RoboCop from the movie of the same name, 1987, directed by Paul Verhoeven
Marvin the Martian from the Looney Tunes cartoons
World of Warcraft orc?
Sonic the Hedgehog from the Sega video games is lining up for the gate
Tracer from Overwatch video game from Blizzard
Grandma from Looney Tunes?
Possibly Nightwing from DC Comics
Hello Kitty, Badte-Maru, and Keroppi running along behind and to the left of Parzival
Parzival's holster is a Han Solo holster with a Thundercats logo on the buckle
Attikus from the video game Battleborn walking away from the camera POV
Protoss zealot on the left, all gold, Starcraft video game from Blizzard, walking with what looks like an IOI agent
There's a guy in all black with a black fedora and huge gold chain around his neck walking away from the camera - this is the first time we see him but he shows up a lot. who?
First zooming in on Planet Doom, there is a huge clash of two armies with giant scorpions coming from the left (Clash of the Titans?) and men mounted on ostriches coming from the right similar to the video game Joust
Aech's gun seems to be an MA5B Assault Rifle from HALO, the video game
Freddy Kruger, from the Nightmare on Elm Street movies, first onscreen kill by Aech
Second kill by Aech is ???
Third kill by Aech almost looks like Man-Bat, DC Comics
Duke Nukem from the video game franchise
Some kind of Emoji-faced guy (the face keeps changing)
Zergling, Starcraft video game from Blizzard
Aech grabs an EM-1 Rail Gun from Eraser, 1996, directed by Chuck Russell
Scorpion?, Mortal Kombat from Midway Games, killed by Daito
Skeletons climbing the hill reminiscent of Harryhousen movies or Army of Darkness
Blob?, from Marvel Comics
Hydralisk, Starcraft
Vegeta?, Dragon Ball Z anime
Stars and Stripes Raynor from Starcraft Heroes of the Storm video game
The robot Raynor shoots (the mom in the bathrobe's avatar) almost looks like a modified Marquis from the Battleborn video game
Posters on the wall behind the girl: Donkey Kong Jr, Bangles album All Over the Place, one next to it and a few above the window I'm missing
A blue Carebear (can't see which)
Jason Voorhees from the Friday the 13th movies
Song: Everybody Wants to Rule the World by Tears for Fears from Songs from the Big Chair, 1985
Donatello and Leonardo on the left, looks like the 2014 and 2016 movie versions of TMNT
World of Warcraft female orc?
Behind the orc, there's someone wearing normal clothes but has a silver mask and helmet on that looks very familiar but I haven't yet figured out why
Doc Brown, back from the future outfit, Back to the Future, 1985
Movie note: 1972 is the mint date on the quarter in focus on Halliday's right eye and is also Halliday's birthday. The quarters in the book were minted in 1984 but no reason is given for this date.
In the funeral scene, Halliday is wearing a Simon electronic game pin on his lapel
Halliday's funeral is a Star Trek themed funeral
Halliday's casket is a MkII photon torpedo from Star Trek II which is draped with a flag of the Federation of Planets similar to how Spock's casket appeared at the end of the same movie.
Halliday sits up in his casket to a creepy music bite - this seems to mimic Dracula sitting up in his coffin in the old Beli Lugosi Dracula movies but I can't find a reference