Eternal Fighter Zero

Eternal Fighter Zero is a doujin Fighting Game made by Tasogare Frontier, who are known for other doujin games such as Higurashi Daybreak and Immaterial and Missing Power. Eternal Fighter Zero stars characters from various visual novels made by Key Visual Arts (and Tactics, before Key Visual Arts split off from them). The original version featured characters from ONE and Kanon. Later versions added characters from Moon and AIR, for a total of 23 unique characters.

The gameplay is based largely off of other popular 2-D fighters, including Street Fighter, Guilty Gear, and King of Fighters. Several of the characters' stances and attacks can be traced to characters from these games, along with many Shout Outs. This game is also known for its many in-jokes and references to the original visual novels. The game has a large cast, but aside from SNK Boss Kanna, the characters are all very balanced, as tier lists don't really make as much of an impact as most other Fighting Games.

This game provides examples of:
 * An Ice Person: Shiori Misaka.
 * Big Eater: Misaki Kawana, referenced in her "High-Speed Lunch" super.
 * Bloody Murder: Ikumi Amasawa, who uses both her own and her victim's blood for various attacks.
 * Blow You Away: Misaki Kawana.
 * Captain Ersatz: Several of the characters take some of their moves, or even their whole fighting styles, from characters in other games. Most obviously, sweet, innocent Sayuri Kurata uses moves based on Rugal Fucking Bernstein!
 * Clothing Damage: Occurs temporarily when hit by a fire attack; all damage is regenerated when the character hits the ground.
 * Combined Energy Attack: Ikumi Amasawa's Final Memory, "Sword of Friendship".
 * Combos: Most notably, using the reinforce gauge to cancel almost any attack.
 * Desperation Attack: Final Memories, which can only be used at less than 1/3 health and with a full super bar.
 * Dinosaurs Are Dragons: Misuzu Kamio's "Gao Gao Fire" super.
 * Drunken Boxing: Parodied with Nayuki Minase, with her sleepy boxing.
 * Extremity Extremist: Kaori with punches and Nayuki with kicks.
 * Fire Breathing Diner: Doppel Nanase does this with ramen for her "Maiden Fire" special.
 * Fire Ice Lightning: Kano Kirishima's tiered spells.
 * Her spells are a Shout Out to the MMORPG Ragnarok Online--The elemental bolts, Soul Strike, Frost Driver, Jupiter Thunder, Storm Gust, etc.
 * Flaming Sword: Mishio Amano's fighting style.
 * Gargle Blaster: Akiko Minase's Final Memory, which features her infamously inedible jam.
 * Guns Akimbo: Makoto Sawatari's "Ground Strafing" super, based off of Dante from Devil May Cry.
 * Harmless Freezing: Shiori Misaka.
 * Heavy Sleeper: Nayuki Minase; she actually has two forms: a sleepy form that parodies Drunken Boxing, and an awake form that unleashes a variety of alarm clocks for her "Special Collection" final memory.
 * High Pressure Blood: Ikumi Amasawa.
 * Home Run Hitter: Rumi Nanase.
 * I Know Madden Kombat: Awake Nayuki Minase, whose fighting style is a reference to her position as captain of the school track team in Kanon.
 * Improbable Weapon User: Almost everyone.
 * Instrument of Murder: Mizuka's cello.
 * Kick Chick: Nayuki Minase.
 * Loading Screen: The game uses a large collection of Fan Art for loading screens.
 * Magical Girl: Sayuri Kurata's character is a reference to the genre.
 * Magic Skirt
 * Magic Wand: Sayuri Kurata has a Magical Girl wand; Kano Kirishima uses a fantasy role-playing game staff.
 * Mana Meter: Kano Kirishima, whose MP bar must be charged in order to cast her tiered elemental spells.
 * Morph Weapon: Sayuri Kurata's magic wand.
 * Musical Assassin: Mizuka Nagamori, can create exploding music notes.
 * Nerf Arm: Rumi Nanase's wooden sword.
 * Precision Guided Boomerang: Mizuka Nagamori's cello bow, in her "Slow & Keying" special.
 * Prehensile Hair: Akane Satomura.
 * Razor Wind: Misaki Kawana.
 * Screwball Serum: Once again, Akiko Minase's Final Memory.
 * Short Range Long Range Weapon: Makoto Sawatari.
 * Shout Out: Lots of references to both the original visual novels and to various other Fighting Games. Makoto Sawatari's stage also features Clannad in the background, a later Key Visual Arts visual novel.
 * See Kano Kirishima's spells above. Also, her staff is a special staff from the same game, called a "Mighty Staff."
 * SNK Boss: Kanna. Subverted on difficulties 1 and 2, where she hardly attacks and generally just waits for you to kill her. Played brutally straight on difficulties 3 and 4. You pretty much need to be an EFZ god to beat level 4 Kanna (or use extremely cheap tactics, but even that takes a lot of luck).
 * Super Mode: Ikumi Amasawa's "Violent Run - Genocide Mode"; Rumi Nanase's "Enduring Maiden's Aesthetic" Final Memory.
 * This Is a Drill: Akane Satomura's neutral fierce.
 * Time Stands Still: Mizuka Nagamori's Final Memory, "Eternal Poem". Misuzu's, too.