The next installment in the Guilty Gear sci-fi fighting series, in which bio weapons called Gears fight among each other for ultimate supremacy and survival, as they escape the so called Holy Knights who aim to hunt down and destroy them.
As with previous games in the series the game involves tournament-styled battles between characters using their special abilities and moves. However for GG Isuka the battles are 2-on-2 instead of 1-on-1, taking place in multi-plane arenas (similar to Fatal Fury) and requiring the players to switch orientation manually.
Added features include two new characters (only one playable), new backgrounds and game modes including the new "Boost" mode, which turns the game into a 2D side scrolling beat 'em up.
Kousaka, one of the main characters from the anime about otaku lifestyle, Genshiken, is frequently seen playing Guilty Gear Isuka. He always plays as Sol Badguy. In episode 4, he wins the Guilty Gear Tournament organized by the Anime Club, receiving "25 years of crap games" as a prize. In the last battle, the character that Kousaka defeated was Jam Kuradoberi. Coincidentally, a short while after the tournament and in the same room, Ohno (another main character from Genshiken) is seen cosplaying as Jam Kuradoberi.
In episode 6, while neglecting his girlfriend, Saki Kasukabe, in favor of gaming, he is playing Guilty Gear Isuka alone with the same characters (Sol Badguy vs Jam Kuradoberi). It seems that the anime creators had a special love for these two because we meet them again in episode 7. Trying to prevent new members from joining the Genshiken club, Saki says she will accept them only if they defeat Kousaka in a fighting game (which is frankly impossible). Accepting the challenge, Sawazaki chooses Jam Kuradoberi, while Kousaka plays his traditional Sol Badguy. Kousaka wins without effort.