Ishigakibaru

The campaigns of the Ishigaki plains took place on the island of Kyushu. The Eastern army invaded the Western army's stronghold, led by Kanbei, to prevent any unexpected surprises at Sekigahara. Many ex-Toyotomi generals participated in these sieges against Toyotomi loyalists. Also, the Tachibana and Shimazu as well as Chosokabe, were providing support for the Western army resistance, led by Yoshimune Otomo.

Samurai Warriors
This does not appear in the first two games. In Samurai Warriors 3, the Eastern version takes place in Kanbei and Kiyomasa's stories. For the Eastern side, a labyrinth of rocks opens, and it  must be quickly infiltrated. Although Kanbei is the commander, Kiyomasa can't be lost as well, otherwise, the ranks will fall into disarray. Masanori also is in the stage, but plays little importance. Once the stone labyrinth is cleared, Yoshihiro and Motochika will need to be defeated as well, trigerring Yoshimune's and Ginchiyo's charge, with Muneshige's reinforcements. For the Western side, it is only available in Ginchiyo's story and the player needs to deflect Kiyomasa and Masanori's overwhelming charge, and allow Motochika, Yoshihiro and Muneshige to arrive as reinforcements to defeat Kanbei. This shares the same map as Kasai-Osaki, although it uses different textures.