House Elliver is a possibly extinct vassal house from the North of Westeros, holding allegiance to House Stark of Winterfell. They are mentioned briefly in Game of Thrones: A Telltale Games Series, to which they are unique.
During a meeting of Ironrath's small council, Lord Rodrik Forrester may ask about summoning House Forrester's allies. Duncan Tuttle responds that House Elliver, along with Houses Grayson and Brownbarrow, were wiped out at the Red Wedding.
In the books
Unlike the Forresters and Whitehills, House Elliver seems to be purely an invention of Telltale, much like Houses Branfield and Glenmore. The same is true for their allies, Houses Grayson and Brownbarrow.
Houses from the North