From 1d4chan
You'd think he worshipped Khorne with all of those skulls.

Valnir the Reaper is one of the original Chaos Champions from the earliest editions of Warhammer Fantasy Battles. A sworn servant of Nurgle, he once led the Marauders known as the Tribe of the Crow and became the soul-gathering Champion known as the Reaper of Nurgle before the Great Chaos War. Cut down by Tzar Alexis of Kislev during the final melee of the battle for the Gates of Kislev, he staggered back to his followers and asked to be buried in his homeland. Two centuries later, Nurgle revived Valnir as a twisted unliving abomination, a rotting corpse sustained by Nurgle's dark power. Taking up the Gatherer of Souls again, his very presence bringing pestilence, plague and famine, Valnir the Reaper has stalked the lands of mortal ever since, the Breath of Nurgle made manifest.

Whispers are that Valnir will be returning as the Nurglish Lieutenant of Archaon as part of the next release for The End Times.

He did actually show up in the End Times only to be decapitated by Wulfrik the Wanderer while the two sparred in order to pass the time until Valten showed up.

The Champions and Lords of the Warriors of Chaos
Aekold Helbrass - Arbaal the Undefeated - Archaon - Asavar Kul - Beorg Bearstruck - Bödvarr Ribspreader
Dechala - Egrimm van Horstmann - Festus the Leechlord - Feytor - The Glottkin - Gutrot Spume
Haargroth - Harald Hammerstorm - Lord Mortkin - Kaleb Daark - Kayzk the Befouled - Krell - Maggoth Lords
Melekh - Mordrek the Damned - Sayl the Faithless - Scyla Anfingrimm - Sigvald the Magnificent
Skarr Bloodwrath - Slambo - Styrkaar of the Sortsvinaer - Tamurkhan - Thorgar the Blooded One - Throgg
Valkia the Bloody - Valnir - Vardek Crom - Vandred - Vilitch the Curseling - Wulfrik the Wanderer - Vorgaroth the Scarred and Skalok