Therefore, in a blatant attempt to take advantage of any possible momentum from the release of the newest spin-off, Arc System Works' 2.5D fighting game DNF Duel, let's take a look at the anime adaptation of this South Korean/Japanese phenomenon... The first one, at least, as I don't think 2020's Arad Senki: Gyakuten no Gear has an English translation of any sort, astonishingly enough.
At the Hangame 2008 Summer Festival, it was announced that Dungeon & Fighter would be receiving an anime adaptation by Gonzo & its Korean subsidiary GK Entertainment, titled Arad Senki: Slap-Up Party, or Dungeon & Fighter: Slap-Up Party in South Korea. Loosely based on the characters seen in the official webcomic at the time, Arad no Hourou Party/The Wandering Party of Arad, the anime would debut first in Japan on April 3, 2009 & last 26 episodes... right as Gonzo was going through some notorious financial troubles. This culminated in Gonzo's parent company GDH absorbing the studio completely (creating the Gonzo that exists today) & being delisted from the Tokyo Stock Exchange on July 30, 2009, right in the middle of Slap-Up Party's run on TV Tokyo (as well as Saki & Shangri-La's runs on their respective networks). However, unlike its fellow Gonzo anime from 2009, Arad Senki: Slap-Up Party has never been licensed for English release yet, not even streaming, though it did at least eventually get fansubbed back in the day. So did the English anime market miss out on something worth watching at the time, or was Slap-Up Party rightfully overlooked, especially since Dungeon Fighter Online wouldn't even exist until another year after this anime debuted?
(That being said, I'll be using the official English terminology, as defined by the official DFO website, where possible)
On the Arad Continent in the year 981, a party lead by a warrior named Aganzo embarked on a quest to kill the monster Sirocco that was causing a series of demonizations amongst the populace, including that of a dark elf Slayer named Roxy within the party itself. The party succeeded, but only after Roxy allowed herself to turn into a full demon, and the resulting kill wound up spreading the phenomenon, now called "Kazan Syndrome" across all of Arad. It's now 994, and Baron Abel is a Slayer roaming the land in search of a cure for Kazan Syndrome, as his affliction resulted in him being cast away from his own village as a child. Inhabiting the great sword he wields, the same one that killed Sirocco 13 years ago, is the spirit of Roxy herself. Soon enough, Baron creates a party of his own with Capensis, a Gunner who claims to be from the "Heavenly Realm" of Empyrean; Ryunmei Ranka, a female Fighter who primarily wants to continue training & fight stronger foes; Ixia Jun, a young elven Mage who had previously been kicked out of a prior party due to her inexperience; & on occasion Jedah Lucsuppa, a burly warrior of a Priest who has a strong fascination with Baron. Along the way, "The Party" also find themselves going up against the Slayer forces of the human De Los Empire, led by Irbek, a member of Roxy & Aganzo's old party who has his own reasons for figuring out the truth behind Kazan Syndrome, and if it can truly be cured.