In the past, I asked how to fight a discard deck, one that's designed to just empty your hand as fast as possible with cards like Hymn to Tourach and many others. I have also read this question on playing around targeted discard.
However, at this point my friend has rebuilt his deck to a very high degree of efficiency. I often lose one of my opening lands to Hymn, and any creatures I get out are killed by targeted kill spells or board wipe like Drown in Sorrow. I never have a chance to play higher cost creatures because my hand gets emptied by discard spells. Lately I've been playing white weenie / equipment with some very good cards like Mother of Runes, Swords to Plowshares, Aegis of the Gods, Jitte, Stoneforge Mystic, and more, but ultimately all my creatures get killed by board clear and my hand is emptied. He will sometimes clear the board 3-4 times before I get killed by a combination of Black Vise, Quest for the Nihil Stone, and Guiltfeeder.
Again, I know discard decks aren't exactly one of the main Legacy archetypes. But I'm looking at decks like Miracles, Jund, D&T, OmniTell, Merfolk, and others, and to be frank, probably because I'm inexperienced with tournaments, I can't see how they would respond to this strategy. (Okay, I see how D&T stops it fairly easily, but not the others.)
How would some of the major Legacy archetypes respond to a discard deck?