As it turns out, Luffy really did eat the sun fruit in canon, specifically a Sun God.
Mihawk tells the Krieg pirates that he destroyed their forces in retaliation for waking him from his nap. Years later the live action adaptation would do the exact same thing.
Nightmare Fuel: The illness that Robin was afflicted with on Little Garden. The fungus that infected her was an ancient strain of Cordyceps that was stated by Dr. Kureha to be outright malevolent. This of course cranks up the nightmare fuel to eleven when you realize that means this fungus can think.
