Shout Out / Afterimage

• In the Heart of Veins, a sword has been planted on a stone. After Renee interacts with it (and it doesn't even budge), Ifree mentions a quick reference to King Arthur and the Sword in the Stone.
  Ifree: Renee, I've heard the tale. Whoever can draw the sword from the stone will become king.
• The "Midas Touch" spell given by the Scroll of Pillage turns Random Drops and currency farming into the player's favor. Its name, ability, and Flavor Text mentioning "greed" are obviously a nod to King Midas from the Greek myths.
• The "Hollow Vessel" accessory is an entire reference to Hollow Knight. It's shaped like the Knight's head. It's found sitting on a bench under a streetlight in Goliathfall, referencing the save points of that game (specifically the one in Dirtmouth). It emits black smoke from one of its eyeholes, referencing the Void. Its Flavor Text mentions a "dying kingdom", referring to Hallownest. Gameplay-wise, it allows Renee to gain MP with each attack, as a nod to the mechanic in Hollow Knight where blade attacks gradually fill up the Knight's Soul gauge.
• Some Achievement/Trophy descriptions are references to pop-culture songs:
  • "Homecoming" - "Where is my mind?"
  • "Dream" - "Sweet dreams... are made of this?"
  • "Cradle" - "Down in a hall and I don’t know if I can be saved."
  • "Hope" - "This fire is out of control..."
  • "Withering" - "...the hardest part of this is leaving you."
  • "World Flower" - "Shine on, you crazy flower."
• There are Achievement/Trophy names that are also straight up references, though some are appropriately used with context, while others may not necessarily need context:
  • "Gate of Babylon" – For collecting all weapons and armor pieces.
  • "Money For Nothing"
  • "For Whom the Bell Tolls"
• The "Holy Whip" weapon bears a striking resemblance to the Combat Cross from the Castlevania: Lords of Shadow games in the Castlevania franchise, by virtue of having an ornate cross-shaped handle with an extendable chain. Its Flavor Text also references the Combat Cross's classical counterpart, the Vampire Killer in the general Castlevania lore; it mentions the weapon's power can purify all "filthy existence" (as a nod to the Vampire Killer constantly being used to fight evil entities), and the weapon was "passed down in generations in a clan" (as a nod to the Vampire Killer being an Ancestral Weapon of the Belmont Clan).
• Some references to Castlevania: Symphony of the Night:
  • The Blade weapon "Anemogrim" is a blatant copy of the Crissaegrim. Apart from the similar-sounding name making it obvious, it's also similar in gameplay and in visual effects; having a relatively low damage per hit, but offset by being able to hit enemies with it really fast (as indicated by curved Sword Lines appearing in front of Renee).
  • "Outfit – 0101" changes Renee's colors to evoke the appearance of Alucard's hair, armor and cape.
  • Agus, the Pyro Goliath has a few abilities or animations that resemble Dracula's from Castlevania games like SotN, the most notable one being the fireballs that he slowly launch forward. His boss arena in Scorchwhere makes the comparison obvious as well, as it contains his throne in the background just like Dracula's throne room.
• "Outfit – 1011" is a primarily white/gray outfit but with blue accents and turns Renee's hair into white. It evokes the appearance of Soma Cruz, the protagonist of Castlevania: Aria of Sorrow and Castlevania: Dawn of Sorrow.
• Renee can learn the "Judgement Cut" weapon skill for the Blade-type (katana) weapons. By its name and weapon association, it's a reference to Vergil's signature charged attack "Judgement Cut" (or "Judgment Cut") with his katana Yamato in the Devil May Cry franchise, though the "Judgment Cut" of this game has a different animation than Vergil's. The more blatant Devil May Cry Vergil reference however is shown near the endgame. Red Renee can perform a powerful attack at low health which involves unsheating the katana, followed by a Flash Step, multiple huge slashes appearing all over the screen, then ending with dramatically sheating the weapon as the boss has their back turned from you. It's a replica or homage to Vergil's "Judgement Cut End" from Devil May Cry 4 and Devil May Cry 5, albeit all the visual effects are colored red to match Red Renee's theme instead of Vergil's blue.
• "The Wall" ending is a reference to The Matrix but presented as a combination of a Joke Ending and an Easter Egg. It's implied that the suspicious telephone booth transports Renee into a different world, much like how the Matrix is a virtual world distinct from the real world, and how Trinity departs from the film's first act via a phone booth. When Renee picks up the phone, countless glyphs start rolling down the black screen as a homage to the film's usage of the Matrix Raining Code. If those weren't clear enough already, the unlockable achievement for the ending has the description of "Red phone or blue phone?", referencing the Red Pill, Blue Pill choice.