Shout Out / The Binding of Isaac

  • Super Mario Bros.:
    • The 1-up mushroom that follows you around is green with white spots.
    • The Magic Mushroom and the Mini Mush are direct references to Mario's Super Mushroom and Mini Mushroom.
    • The Bobby-Bomb walking bomb upgrade is a clear reference to Bob-Omb.
    • One of Rebirth's items allows you to jump. What does it look like? A copy of the original Super Mario Bros.
    • Rebirth has an item called Gnawed Leaf that gives Isaac a raccoon tail and lets him turn into a statue.
    • The description of the Liberty Cap is "Touch fuzzy, get dizzy".
    • One of the messages dispensed from the Fortune Teller is "Your princess is in another castle".
    • Collecting enough mushrooms in Afterbirth turns you into a mushroom-person, strikingly similar to a Toad.
  • The Legend of Zelda:
    • The HUD and basic rooms are very blatant ones to The Legend of Zelda.
      • In Rebirth, alternate trapdoors can send you to underground rooms that are just as blatant.
    • Many enemies are also reminiscent of Zelda enemies. The most noticeable are the Chargers (which behave like Ropes) and Knights (which behave like Darknuts).
      • Rebirth added Mom's Hands (which behave like Wallmasters) and Bonies (which behave like Stalfos).
    • Teleportation items may randomly send you to a room with a guy saying "I AM ERROR."
    • Wrath of the Lamb's candle is pulled straight from The Legend of Zelda.
    • The Stepladder from the original Zelda's functionally identical counter-part, simply called "The Ladder."
    • Chub can be made to eat bombs to damage her, just like the Dodongo. Rebirth even adds a "Chub dislikes smoke!" line.
    • Afterbirth adds a new challenge called "I Rule!", which gives you the starting items of a sword, a shield, the Ladder, and the Boomerang.
  • Meat Boy:
    • One of the endings: Isaac dresses as Dr. Fetus from Super Meat Boy, complete with the stage title theme from that game. Unsurprisingly, the ending gives you the Fetus in a Jar powerup. There's also a power-up called "Doctor's Remote," which is another reference to the character in question.
    • C.H.A.D. can appear as an alternate version of Chub.
    • Meat Boy himself appears as a familiar when you collect Cubes of Meat, and Wrath of the Lamb adds a "SMB Super Fan" circular saw item that transforms the player character into a Meat Boy lookalike.
    • The Larry Jr. boss is presumably related in some way to Larries' Lament from the second-to-last world of Super Meat Boy - possibly meant to be the miniature versions of them that pop out of their head in the ending.
    • Rebirth has Bandage Girl appear as a familiar when you collect balls of bandages.
    • A more meta one: the achievements for completing floors without getting hit in this game follow a scheme of "____ Boy", which is the same pattern that the achievements for completing worlds without dying in Super Meat Boy followed.
    • One of the new bosses introduced in Afterbirth is Little Horn, not to be confused with Super Meat Boy's Little Horn.
  • Magic: The Gathering:
    • One of the powerups you can get from the Devil Room in Wrath of the Lamb is "Spirit of the Night", which changes Isaac's face to look like the card of the same name.
    • The Beginner Deck item in Rebirth is a reference to pre-built decks, and it tattoos the "color pie" on Isaac's forehead whenever you take it.
    • Rebirth also adds the iconic "Black Lotus" to the list of items you can get.
    • Also from Rebirth, we have the Chaos Card, which is a reference to the infamous Chaos Orb.
    • From Afterbirth, the Rag Man enemy was inspired by the card of the same name.
  • The Wrath boss is basically Bomberman. In addition, players will occasionally find a room styled after the mazes from Bomberman's multiplayer filled with bombs to collect.
    • Adding to this, the Afterbirth expansion adds the item Bomber Boy, which makes bombs explode in the Bomberman cross fashion.
  • Steven, a tiny head that grows out of your skull. He also appears as a boss.
    • His unlocking is the secret "something from the future", obtained by completing the basement 42 times.
    • For some reason, The Stinger of the final ending tells you to get in the box. In fact, Isaac's relation with the chest and who is inside it is reminiscent of Steven and the box.
  • Many of the multiplayer baby partners are shout outs, including many different Tetris blocks, Optimus Prime, Aban Hawkins, Spelunky Guy, Captain Viridian and Upside-Down Captain Viridian, Dr. Fetus, and Steven again.
  • A number of internet meme faces make an appearance, particularly the Forever Alone and Troll Face, with the latter appearing on bombs which are ready to go off. And let's not forget Shoop-Da-Woop!, which is a charged laser weapon. There is also an enemy type with a distinctive trollface that will split in half upon receiving enough damage, and the duplicates will split further into even smaller copies, demonstrating the spirit, as well as appearance of the trollface. In its smallest form, it becomes a Pokerface. Occasionally, the corpse sitting in one of the secret rooms will be sporting the "forever alone" face as well.
  • One enemy type is the same species as Gish. Gish himself can appear as a boss as well, and drops a baby version of himself (a familiar whose shots slow enemies) when defeated.
  • The "Pills Here!" message after picking up a pill is a shout out to Left 4 Dead.
  • One effect that pills can give you is "Balls Of Steel," which gives you 2 soul hearts.
  • The null effect for pills is "I found pills!", with the fake effect "And ate them". This is likely a throwback to an early LOLCat macro.
  • The "My Little Unicorn" item seems to be a shout out to My Little Pony.
  • The "Technology" upgrade is a clear reference to the Borg.
  • That fly that buzzes around your head to intercept bullets is Pretty Fly (for a White Guy).
  • The shovel item that lets you skip a floor is called "We Need To Go Deeper."
  • The Parasite power-up resembles the Parasite from the Flash-Game "The Visitor" from fellow Newgrounds contributor Zeebarf.
  • When going into the One-Winged Angel form accessible through one of Eve's starting items, the transformation is denoted by the phrase "What a whorrible night to have a curse."
  • One of Death's attacks is scattering spinning sickles all over the room, which fly towards the player. In Rebirth, the player can find Death's Touch, which turns tears into the very same sickles.
  • One of the projectile upgrades is bloody tears.
  • One of the new items in Wrath of the Lamb is the Notched Axe, a pickaxe that can be used to break rocks. This is a double reference, shouting out to the Notched Pickaxe from The Elder Scrolls V: Skyrim, which was itself a reference to Minecraft and its creator, Notch.
  • The Chemical Peel item will give you a Harvey Dent makeover.
  • An item named "Telepathy for Dummies," looking exactly like any "For Dummies" book would look like.
  • One of the messages you can get from the Fortune Teller is "Look to La Luna." This was the clue on how to find Reptile in the original Mortal Kombat game. Two others, "MARRY AND REPRODUCE" and "STAY ASLEEP", reference They Live!. It's also possible to get "I feel asleep!!"
  • Subverted in the case of Gluttony. A lot of fans think that his appearance and the blood-laser that shoots from the stomach are references to Fullmetal Alchemist; HOWEVER, Edmund McMillen himself has stated several times that the resemblance is purely coincidental, because he has never watched (nor even heard of, prior to the game's release) Fullmetal Alchemist.
    • Similarly, the Sad Onion is also not a reference to Stuart Ashen nor the "Not for ages 0-3" face that repeatedly appears on the packaging for products he reviews.
  • The Necronomicon's cover (which looks like a distorted or disfigured face) is the same as in Evil Dead.
  • The Wire Hanger item is a reference to the film Mommie Dearest, in which an abusive mother screeches the famous quote: "No more wire hangers ever!"
  • One of the new items in Binding of Isaac: Rebirth, is the Ludovico Technique, which leaves Isaac's eyelids pulled back, as in the classic scene of Alex's reprogramming.
  • The Dople (a skinless Isaac's doppelganger in The Womb) is a reference to Tomb Raider, where a skinless enemy who mirrored Lara's movements had to be killed by being lured into a lava trap, similar to how Doples can be lured into spikes.
  • Two new pill effects in Rebirth are "Lemon Party" (a reference to an infamous Shock Site) and "R U A WIZARD". (Lemon Party drops a very large, very damaging Lemon Mishap puddle, while R U A WIZARD gives Isaac temporary Fish Eyes that force him to fire each shot at a 45 degree angle instead of straight ahead.)
  • Actively defied in one particular case. Many people were expecting references to Northernlion, Bisnap, or other big names in the TBoI fandom, but Edmund has stated that he intentionally avoided such references in case he accidentally left someone out.
    • Although, there's a little nod to a certain meme started/nourished by Northernlion. "Rebirth Got Canceled" is one of the new Fortune Teller message, which was a popular joke statement back before the game's release,note  and a thinly-veiled Take That towards Phil Fish, who decided to cancel Fez 2 after a particularly bad meltdown.
  • The "Anti-Gravity" item in Rebirth makes Isaac light blue, with white eyes and an atomic insignia on his forehead.
  • Samson's Chains in Rebirth attaches a ball-and-chain to character, like in NetHack or Spelunky.
  • In Rebirth, picking up the Transcendence item gives the message "We all float down here..."
  • One of the fortunes you can get is "Nobody knows the troubles you have seen"
  • One of the card items in Rebirth is A Card Against Humanity. It fills the room with poop when you use it.
    • On the Easter Egg front, the card you pick up is a Black card with the caption "Something stinks...". When you unlock it in a new save, the card shown is a White card saying "a room full of poop."
  • A new item that appears in the Afterbirth DLC, the Friend Ball, looks like and functions similarly to a Pokéball.
  • The Afterbirth DLC contains an item called "Continuum". Its effect allows Isaac's tears to loop through the boundaries of the screen.
  • Lazarus is characterized by his red hair. Much like another fictional character who uses the name.
  • Crack The Sky is a reference to King Lear, but also to an album of the same name by Mastodon.
  • Two new pills added in Afterbirth are "One Makes You Larger" and "One Makes You Small", referencing the Jefferson Airplane song "White Rabbit". Presumably they'll still work if you get them from Mom's Coin Purse/Mom's Bottle of Pills, though.
  • Afterbirth added an item called Black Powder which lets you draw circles of (what else?) black powder to form pentagrams that deal damage to enemies standing in the area. Its in-game hint text? Spin the black circle.
  • Spider Mod is a reference to Spidermod, an extensive Game Mod for the original The Binding of Isaac. Its creator, Spider 853, was a lead-developer for Rebirth.
  • The description for one of the new items in Afterbirth, the Lil' Chest, reads What's in the box?
  • The Forget Me Now item is a reference to the series Arrested Development.
  • My Shadow, one of the new items in Afterbirth, has a description that says "Me! And my shaaaaaaaaaadow!"
  • The icon of one new item in Afterbirth, Zodiac, is very similar to the symbol the serial killer known as the Zodiac killer used to sign his taunting letters to the police and press.
  • There are 3 very hard to unlock items called The Body, The Mind and The Soul. Their descriptions are respectively "I feel all", "I know all", and "I am all". They are a reference to the movie Highlander, as the three are said almost verbatim when MacLeod wins The Prize.
  • A new item in Afterbirth are the 8 Inch Nails.
  • Another new item in Afterbirth is the Ventricle Razor, which lets you spawn blue and orange trapdoors that you can warp between.
  • One possible reference might be the Dead Boy achievement, earned by not taking damage in the Chest room or its Dark Room variant. The Chest is famous for having the great big golden door that leads to the Lamb. Life has many doors, Dead Boy!
  • From the wiki's page for GB Bug:
    The pickup quote "Game breaking bug, right away!" is a reference to a quote by Phil Fish in Indie Game: The Movie, where he says the exact same words when a bug is discovered in FEZ on the first day it is being shown at PAX. This has been confirmed by Edmund himself on twitter.
  • The description of the Louse (a trinket) reads: "Itchy. Tasty..."
  • The second phase of the boss Satan has a significant resemblence to the Icon of Sin.

http://tvtropes.org/pmwiki/pmwiki.php/ShoutOut/TheBindingOfIsaac