Mika recognizes the markings on the tusk as Angmarim sorcery in a Gauradan hand. He wishes you to find and defeat the Gauradan seer who dares try and twist one of the Lossoth's mammoths.
'This is not good. This tusk was marked by the hand of one of the Susi-väki, but the words of power used are Angmarim. This tallies with what I know of a Susi-väki seer who has been seen nearby recently. A Man of Angmar must be trying to teach the Susi-väki how to ensorcel our Norsu!
'I have heard tales of the evil fetters Angmarim place upon their beasts, twisting them into fell creatures through time and despair. This must not be permitted in Länsi-mâ. Find and stop this seer!'
Search around Norsu-hauta for the Gauradan seer who is trying to ensorcel a mammoth.