Superheavy Samurai General Sango

 Pendulum Effect
    If you have a Spell/Trap Card in your Graveyard, this card's Pendulum Scale becomes 4. Once per turn, when a "Superheavy Samurai" monster you control destroys an opponent's monster by battle: You can activate this effect; it can make a second attack in a row.  

Monster Effect  
  If you have no Spell/Trap Cards in your Graveyard: You can Tribute up to 2 "Superheavy Samurai" monsters you control; draw the same number of cards you Tributed. You can only use this effect of "Superheavy Samurai General Sango" once per turn.