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There are several zips/screen wraps and out of bounds travel spots in the game that can be performed with Shovel Knight, Plague Knight, and Specter Knight. Each Knight has the ability to perform them in different areas in different ways, with some not being intended by the developers and patched out to prevent them from happening during casual play, while others that they saw as being hard to pull off by first-time players were left in and are still used by the game's speedrunning community (as of September 2021).

Shovel Knight can perform the "Bubble Wrap" zip in the Plains of Passage by bouncing off of one of the Bubble Dragon's bubbles, causing the game's camera to try and follow Shovel Knight by pushing him through an off-screen transition into the room directly above the Bubble Dragon.

Plague Knight can perform similar harmless "Room Zips" in one area in the Iron Whale by bursting, jumping, bursting again, followed by two uses of the Staff of Surging to access a secret room with a Music Sheet, and when boarding the Flying Machine by using a combination of the Vat and Burst Jumping to skip two vertical screens and the challenges within them. In previous versions of the game, Plague Knight could preserve their momentum before entering a boss room, allowing speedrunners to set themselves up by triggering the opening dialogue to a boss fight in more advantageous spots than normal. This would be patched out later to prevent unexpected results, but still allowed a brief window for players to perform any action, including bursting forwards to bosses anyways. All characters may do any action frame perfectly after the transition, including pausing.

Specter Knight used to be able to perform a transition in the second stage of the Tower of Fate ("????" in New Game + only). Normally, Specter Knight can perform an easter egg by jumping off of a ledge in the Tower of Fate, but will not lose money and trigger a cutscene with either Dark Acolyte or Reize. However, the plane that triggers this death used to be low enough that Specter Knight could float underneath a nearby ledge precisely and use that as a screen transition to enter areas the player is not supposed to go to yet. In a later update, this plane was raised to prevent this glitch from happening, but Specter Knight does have a glitch that was intentionally left in by the developers. In the Lost City, a trick called "Lost Spaghetti can be performed in one area by having Specter Knight turn the lava into bouncy goo while he is falling in. If done right, Specter Knight should fall just below the plane where he would bounce on the goo and harmlessly phase through it into the room below, missing the death plane normally assigned to the lava.
Contributed by MooMooAkai
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In earlier releases of the game, Specter Knight can double jump with some complicated inputs, two walls very close together, and the use of a curio that doesn't halt his momentum. This glitch would later be patched out.
Contributed by MooMooAkai
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Plague Knight can achieve super speed by combining a fleet flask with a bomb burst, but only while the cheat code that enables God Mode is activated ("STQQTXVX"). This glitch can cause various softlocks due to it providing far more speed than the game expects the player to have, and can break cutscenes and lure bosses outside of their arenas.
Contributed by MooMooAkai
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It's possible to have Scarlet's Skull in the same room as Red, the NPC who is searching for her. Under most circumstances, Scarlet will be the 80th Skull to collect, but the game's developers took some careful measures to try and prevent her Skull from being the one in the same room as him. However, if you collect the other Skulls in the Tower of Fate, such that Scarlet's Skull is the 80th or 81st, the remaining Skull in the same room as Red is forced to be Scarlet's Skull.
Contributed by MooMooAkai
In the Plague of Shadows campaign, during the penultimate boss fight Spoiler:against the titular Plague of Shadows inside Plague Knight's mind, you can defeat it by standing still and doing nothing for around 40 seconds, because the boss cannot hurt you in the spot you stand in at the very start of the fight. After this time has passed, the boss (labelled as "????" in the game's text box) will say:

????:Spoiler:YOU ARE STEADFAST IN YOUR RESOLVE... MAYBE THERE'S HOPE FOR US YET...


before transforming into its second form and the campaign's final boss fight, Spoiler:the Corrupted Essence.
Contributed by MehDeletingLater
While pausing the game during a meeting with the titular characters of Battletoads in the Xbox One version of the game, the pause menu theme from Battletoads will play.
Contributed by CuriousUserX90
According to Sean Velasco and David D'Angelo, as of November 2019, the Nintendo Switch port of Shovel Knight accounts for 25% of sales of the game, despite being released several years later.
Contributed by PirateGoofy
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The Shovel Knight amiibo figure, which is compatible with the Wii U and 3DS versions of the game, is the first amiibo to be able to function whilst still in its packaging, unaltered. This is because it doesn't include the blocking strip which can be found in every other amiibo packaging. Yacht Club Games made this intentional after receiving feedback from fans who wanted to keep it as a collector's item.

The figure is also the first amiibo to be produced not by Nintendo's own manufacturers. The game itself was also the first non-Nintendo developed title to receive its own amiibo.
Contributed by KnowledgeBase
The feat called "only you", which requires the player to dig up campfire ashes, is a reference to Smokey the Bear and his catchphrase "only you can prevent wildfires"
Contributed by ghostkiller
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Vitas Varnas, actor, occasional Game Grumps contributor and writer for VGFacts and Did You Know Gaming?, appears as a portrait in the Hall of Champions. People who had pledged $200 or more to the game's Kickstarter would have a portrait of them appear in-game.
Contributed by Dazz
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Matt, from the let's play series TwoBestFriends, appears as a portrait in the Hall of Champions. Anyone who had pledged $200 or more to the game's Kickstarter had a portrait of them put up.
Contributed by KnowledgeBase
The traveler bosses that Shovel Knight encounters were created by backers who had donated $1,000 or more to the game's Kickstarter. The traveler bosses were created by the following pledgers:
• Reize by Danny D. Henderson
• Mr. Hat by Alexander Hatzikides
• Baz by Matt and Woolie
• Phantom Striker by Steven Ness

The enemy Liquid Samurai was created by Max VanDuyne.
Contributed by KnowledgeBase
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The wandering boss Baz was based on an unused character design from Street Fighter II referred to as 'Zubaz'. Baz was created by Matt and Woolie of the let's play series TwoBestFriends as a backer reward for pledging to the game's Kickstarter. Baz has appeared in multiple games which Matt and Woolie have put him in as a Kickstarter pledge incentive.
Contributed by KnowledgeBase
All the music for the game was composed on Famitracker, a program which creates music for the NES. This means that the music can be played back on an actual NES, and the composer, Jake "Virt" Kaufman, has released the .nsf file that can be played back on a real NES using a flash cartridge.
Contributed by snesiscool
Shovel Knight has over 300 cheat codes. These can be activated by inputting a certain combination of letters into the name selection screen when starting a new game.
Contributed by Makzu
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After defeating all of the Order of No Quarter in the Tower of Fate: Ascent level, if you save the Knights and then talk to King Knight whilst wearing the Ornate Plate armor, he will compliment Shovel Knight for assumingly copying his style.
Contributed by KnowledgeBase
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If an investor pledged $200 or more on the Kickstarter page for Shovel Knight, your face would be included in the level 'Hall of Champions'. One of these donators was Arin 'Egoraptor' Hanson, animator and co-host of Game Grumps. Because Arin forgot to send his face to the development team, they instead used his appearance from Game Grumps.
Contributed by Makzu
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If you enter "WSWWAEAW" at the name entering screen, it will activate a cheat that will turn most of the words "shovel", "knight", "health", "mana", and "fate" into the word "butt".
Contributed by alienator2013