Chaos Wars

 is a tactical role-playing video game released by Idea Factory for the PlayStation 2 in Japan on September 21, 2006. Promotional art for the game is by Kinu Nishimura. The game's opening theme "Shūtan no Ou to Isekai no Kishi ~The Endia & The Knights~" was done by Sound Horizon. In North America, the game was released on June 3, 2008 as a GameStop exclusive. 
"Chaos Wars" is a crossover between several companies' role-playing video game series, including Aruze's "Shadow Hearts", Atlus's "Growlanser", Idea Factory's "Blazing Souls", "", and RED Entertainment's "Gungrave" and "Code of the Samurai".
"Chaos Wars" has become a cult classic because of the poor voice acting in the English localization of the game. Due to the voice actors sharing last names with members of the publishing team, it's believed they were relatives of the team.
Story.
Hyoma, the protagonist, has a dream of another world over a pillar of light coming from his family shrine that has been missing since his ancestor's time. The next day, he decides to take his two friends, Shizuku and Hayatemaru, to investigate the mountains where his dream took place. During their investigation, they find a cave with strange technology but as they are looking into it, the machines activate and a bright light appears, taking them to another world known as Endia.
When Hyoma transports to the world, he encounters a girl named Rin, the Gatekeeper of Endia, who is surrounded by summoned monsters. After Hyoma helps defeat the creatures the two introduce themselves, Hyoma rudely interrupting her and instead asks how to return to Tokyo. Before Rin could explain, more monsters appear. Hyoma and Rin run together, where they meet up with a friend of Rin's named Hiro. Afterwards, once safe, Rin explains that the walls are thick in this world, which is the reason that they have been taken from their world to this world. They are known as "Knights" because when people are taken to Endia, they obtain powers like any other.
When Hyoma asks how to get back to his world, Rin explains that there is no way to return. Hyoma doesn't accept this fact and decides to find a way, but there, they then encounter the "Luin", an Organization that is determined to find "Keys" (mechanisms used to open gates and to summon "knights") in order to make their "paradise". After they escape from them with the help of Rin, they are taken to an isle near another island named "Radiance Island". There, they find a vacant mansion with its own transporter and that is where their adventure begins.
Reception.
"Chaos Wars" received "mixed" reviews according to the review aggregation website Metacritic. IGN commented that, "In truth it's probably one of Idea Factory's best efforts released here in the States, melding staples of the genre with more open, zippy little ideas." On a negative note, " said: "Chaos Wars" might draw in some--like fans of the obscure games it's based on, especially those who long for the days of hand-drawn characters and tiny battlefields--but its old-school aesthetic isn't enough to make up for the lackluster production values and uninspired game play." In Japan, "Famitsu" gave it a score of two sevens and two sixes for a total of 26 out of 40.