(This is not the exact form in which you fought him, but it is pretty close. He has had a few item downgrades and a few item upgrades/additions, most notably of winged boots and a ring of evasion; two feats were replaced as well so as to make taking thicket of blades legal. His challenge rating is one more than his class level due to the fact that he has a decent amount more wealth than a typical 17th-level character, plus he has above-25-point-buy statistics and four arms.)

The Lord of Blades