The Creaking Skull is your first major challenge. It's a large skeleton that attacks with its fists and by summoning smaller skeletons. Equip your strongest weapon and any useful Bullet or Guardian Souls you've acquired (Zombie or Skeleton souls are good for ranged damage). Focus on dodging its slow, telegraphed punches. When it summons smaller skeletons, quickly dispatch them to avoid being overwhelmed. After defeating it, you'll gain access to the next area: the Study.
