Going in for the Kill!

Keppuu Ren - Attack
The Keppuu-Ren (Blood Wind Clan or Blood Style Party) are the personal warriors/assassins of Doki the Direct Descendant.

Originally from Tsuchioni/Doki of the dark(闇の土鬼), the Keppuu-Ren were lead by Four Kings until the Direct Descendant arrived. No mention if these Kings were incorporated into Imagawa's GR Universe.
* View GR Spoiler *
Rumor is that the Keppuu-Ren Clan might be just a 'psychic' extension of Doki. This may explain the Keppuu-Ren's protective behavior of Doki and why Doki can not enter a battle until the last member is slain. And how does one explain Doki's psychic power? Well, part of this rumor also claims that Doki is Big Fire's younger brother...

Keppuu-Ren Screen Grab
Actual Scene - Episode 7
Alt Image(s): 
Keppuu Ren - Attack Sketch