Self-Damage decks deliberately damage their own creatures or life total because another ability turns that apparent drawback into an advantage. The damage might trigger card draw, counters, reflected damage, or other effects.
Blasphemous Act becomes especially frightening beside Stuffy Doll or Brash Taunter, while enrage creatures such as Ripjaw Raptor reward smaller controlled bursts of damage. Sometimes hurting yourself is simply the shortest route to hurting everybody else.
