I want to defeat the Eye of Cthulhu, but I think I'm unprepared. What do I need to defeat him?
Similar to this question, except I am asking about the more difficult expert mode, as opposed to the regular mode.
What I personally used in the fight was
Good luck with the eye! The shield is amazing, totally worth the prep for it.
I've soloed the eye in regular, no armor, only the bees knees. My suggestion, Hermes boots(warding) your best armor(platinum if not molten, meteor, or shadow/crimson) bees knees, about a stack of healers (regular if not minor) a stack and a half of arrows, and any other equips with warding modifiers.
Most efficient way I know of.