The Mask of the Father (and the other 'family masks' gained from defeating Pinwheel in Dark Souls) coupled with the Giant set was a staple of an armor choice for players that opted to use heavy armor in the origional game and has become a popular meme regarding strength builds in the Dark Souls franchise. With the recent addition of Ornstein's Plume to the player model of the helmet in Dark Souls 3 as a result of petitioning and complaints and asking via platforms for the community to make its voice heard, it only seems right that such an iconic armor set and asthetic choice be added back to the final game in the series. In addition to the set adding even more customization options to the player, call-backs such as the famed Zweihander, Grass Crest shield, Black Iron Tarkus set, Solair (iron) set and the Ornstein and Smough's sets add to the overall enjoyment of the game and the addition of the Giant set and the family masks-or at least the Mask of the Father- would fit in perfectly with such legendary and nostalgic sets. As to how this may be achieved; perhaps a new invading NPC can be added to an area, or the set can be added at a location within the Ringed City and the mask(s) in another, or perhaps the Shrine Handmaiden can sell them after picking up the "Giants ashes" which can be added next to the dead Giant blacksmith in Anor Londo to pay homiage to that fallen race. Any justification you could possibly choose to add the Giant Set to the game would undoubtedly have a likewise response gotten from the Ornstein Plume update. The Legend lives on.