Where is The Deer?
Children of Danu
Is dropped by The Cursed
"Investigate Ardmel Trade Post in eastern Ulster, east of Lough Beg."
The Clue is right at Ardmel Trade Post in the north.
The Deer Location
He can be found extorting villagers on the northern shore of Ulster Lake in the port of Inch Lough Neagh.
You can now mark and defeat him.