Troll champion-1-
It is by no means true that only humans were chosen to be the slaves of the Runes, they just made up the largest number.

Ump is one of the first trolls who was forged to the Runes. His spirit scarcely tries to understand the Runes activity, but he understands that he will continue to rise in order to crush any one of his enemies. He will patiently follow his victim and keep returning until the last one is slain and this is why he seldom sees the need to hurry.

In a murderous frenzy he is overcome with the will to destroy like all trolls, but his long life has made him calmer and more cooperative than most of his kind.