Lancel Lannister

A young Lannister cousin, appointed the king's squire, whose entire historical significance is a wineskin. On the hunt in the kingswood he kept Robert's cup filled with a strongwine far stronger than the king was used to, on the queen's instruction, until a man who had killed Rhaegar Targaryen could not manage a boar.

He was too young and too frightened to refuse and spent the rest of his life buckling under it. If you are looking for the murder weapon that killed Robert Baratheon, it was not the tusks.