Kishin Houkou Demonbane

Demonbane is a series by Nitroplus with mecha and Cthulhu Mythos elements. Beginning as an eroge visual novel for the PC, it was ported into a PlayStation 2 non-eroge remake, and spawned a sequel visual novel, a prequel novel, an anime television adaptation and a conversion to manga. An English version of the original Demonbane PC game has been released by JAST USA. The anime is streamed with English subtitles by CrunchyRoll.
Kishin Houkou Demonbane is the PlayStation 2 port of the original, published on July 1, 2004, the title loosely translates to “Roar of the Machine God Demonbane”. Both the anime and the manga adaptations are based under this title, as well as using it in their adaptations. The game was also bundled with a one-episode OVA.
Mix equal parts of science, sorcery, and mechs and one comes up with a cauldron full of something similar to Demon Bane. The game is a set in a contemporary civilization but magic threads throughout the world along with technological wonders such as huge robots which fight for their respective masters. Based on our quick test drive this morning, the cast of characters is extensive and the storyline revolves around a secretive faction who uses magic to unleash a destructive force which ripples throughout a town and destroys a good chunk of it. To combat this underground cabal, a team is assembled which uses a powerful mech as their ace in the hole. Although the mechs on both sides do most of the fighting in the game, the cast of characters also wield magic for offensive and defensive use.