He challenges you in the ways of old which translates to:
"Im calling your ass out, I challenge you, but first, let me send out all my minions and a robo-spider to kill you and I'll just keep running away when you hurt me too much.
Oh...there's no more places to run an- .....thats a nice gjallarhorn you have there....."
-
Super easy except for that hallway he appears in after spider tank and everyone bum rushes in there to give him damage and the solar burn just rekt them