Ligessauc
A knight, the son of Eliman, who murdered three of Arthur’s knights.
Arthur chased him down, but Ligessauc sought refuge in a church, where he was harbored by the beneficent Saint Cadoc for seven years. Eventually, Saints Cadoc, David, and Teilo mediated with Arthur, who agreed to accept one hundred cows in payment for the deaths of his knights.
Ligessauc appears in the Triads as one of the Three Seafarers of the Island of Britain.
Sources
Life of St. Cadoc | Lifris, late 11th century
Triads of the Island of Britain (Welsh ”Triads”) | 11th century to 14th century