Kori Kombat

 xIXRkq-Ybe0?t=25 The trope depicts a rivalry or conflict between the yokai of kitsune and tanuki. These two creatures from Japanese folklore have similarities, such as shapeshifting, casting illusions, and a penchant for being tricksters. There is a name for these events for when these two tricksters fight called Kori no Tatakai (translates to Battle of Tanuki and Kitsune). The name of Kori comes from the kanji of kitsune (狐) and tanuki (狸) put together to make the work, kori (狐狸). Different from a battle of violence, they have a showdown with their shapeshifting powers as a demonstration of their magic. When comparing the two, kitsune usually overpower tanuki through their power, but tanuki are better tricksters. The trope in media doesn’t usually have a battle but more so a rivalry between two magical beasts. A typical example would be a rivalry between two characters who are one of the respective yokai.

Compare to Fur Against Fang in fiction derived from European folklore.

Anime and Manga

 * The fight between Naruto and Gaara seems to be a reference to this rivalry. They are both Jinchuriki for the Fox and Tanuki Tailed Beasts.
 * Averted with Ponchi and Konchi, from Shaman King, most likely due to being Guardian Ghosts to their Shaman.
 * Pom Poko has an example of how the kitsune have hidden amongst humans while using their transformation abilities to make money. While the tanukis rather live in the forest despite the threat of urbanization.
 * Subverted in BNA with Michiru Tanuki and Nazuna Kitsune. The two girls have been human until recently and transform into Beastmen. Both of them have similar shapeshifting powers while also showing similarities to the yokai of their surnames.
 * In Ugokie-Ko-Ri-No-Tatehiki (translates to Moving Picture - Fox vs. Tanuki, Pulling Pranks), a tanuki father and son plague a man who turns out to be a tanuki.
 * In Gugure! Kokkuri-san, Kokkuri-san (a kitsune) acts as a legal guardian for Kohina. He has a strained relationship with the tanuki, Shigaraki, who is quite troublesome as he often gets drunk, gambles, or causes trouble in other ways.
 * In The Rising of the Shield Hero, there is a race called Demi-Humans, humans with bestial traits. The two races of Demi-Humans of the Kitsune and the Tanuki, both specialize in illusion magic. In the past, the Tanuki managed to seal the Kitsune's great Yokai through deception and sorcery.
 * Kitsune no Yomeiri has an event between tanuki and kitsune as a prank war every year where two representatives prank random people, and a winner is determined by who punked the most people. The main heroine, a kitsune, is chosen as the representative to compete with the tanuki's representative.

Oral Tradition, Folklore, Myths and Legends

 * In Japanese folklore, the Kitsune and Tanuki have been rivals since ancient times, whenever they do battle, it usually results in a combat of magical powers and to see who can outwit and outdo each other.
 * Especially when Danzaburō Danuki meddles in, also in part, because he made Sado Island into a Tanuki paradise, kingdom, and sanctuary.

Video Games

 * Referenced in Samurai Warriors with Ieyasu Tokugawa associated with tanuki and his rival, Mitsunari Ishida, related to kitsune.
 * As seen in the video above, Tom Nook and Redd, from the Animal Crossing series, are both based on a tanuki and kitsune. They were once business partners, but their methods contrast each other. Tom Nook often may trick others with fast talk into paying for products and houses but are functional wares. Redd, on the other hand, lies to sells his wares while grifting them when he gets the chance.
 * In Kirby's Dream Land 3, Pon and Con are a tanuki and a kistune respectively. But instead of fighting each other, they're fighting against you and serve as a Dual Boss in the vein of recurring Kirby villains Mr. Shine and Mr. Bright.
 * In Super Mario 3D Land, Mario gets a Tanuki suit when he touches a Super Leaf as one would expect, but when Luigi touches one? He gets a kitsune suit instead that functions exactly the same (wagging their tails to slow their fall, allowing them to make some impressively long jumps). While they deeply love each other, the RPG's and a few sports titles show that there's definitely a healthy bit of Sibling Rivalry going on between the two.
 * Touhou has the Tanuki-based Mamizou Futatsuiwa and the Kitsune-based Ran Yakumo, who utterly hate each other's guts. Playing on an old Japanese myth, Mamizou is even meant to be a stand-in for Danzaburou of legend and is responsible for kicking out all the foxes from Sado.