In total , Kawaguchi 's forces lost about 830 killed in the attack , including 350 in Tamura 's battalion , 200 in Kokusho 's battalion , 120 in Oka 's force , 100 in the Kuma battalion , and 60 in Watanabe 's battalion . An unknown number of wounded also died during the withdrawal march to the Matanikau . On and around the ridge , the Marines counted 500 Japanese dead , including 200 on the slopes of Hill 123 . The Marines suffered 80 killed between 12 and 14 September .