Gyūki

The Eight-Tailed Beast is currently one of the two remaining Tailed Beasts that was not extracted by Akatsuki, while the other one being the Nine-Tailed Demon Fox. Due to Akatsuki's depleted numbers, Madara Uchiha ordered Team Hawk to capture the Eight-Tailed Beast. The host is a musclebound Cloud ninja who appears to dislike light. He also carries eight swords and on right shoulder there is a tatoo that says iron plus on his right cheek there is a picture of a bull's horn.
 * Name:
 * Creature Type: Unknown; appears to be a cephalopod of some sort
 * Host: Unknown
 * Unique Traits: Unknown
 * Status: Active

Speculation
this jinchuurichi could be the one that Yugito Nii(the nibi jinchuuriki)was talking about being the strongest shinobi in the village.As most of the other Tailed Beasts are based upon mythological creatures, it is speculated that the Eight-Tailed Beast is based upon the eight-headed and eight-tailed dragon, Yamata no Orochi.But from the shadow when Sasuke goes to retrieve the beast, it seems to be an octopus.