Self-Discard decks deliberately discard their own cards to improve card selection, pay costs, or enable mechanics that function from the graveyard. The discarded card is often intended to remain useful rather than simply becoming lost material.
Madness cards such as Fiery Temper can be cast as they're discarded, while reanimation decks happily pitch enormous creatures for later revival. Archfiend of Ifnir turns cycling and discarding into control over opposing creatures.
