Eye of Cthulhu
The Eye of Cthulhu Boss from Terraria in Minecraft !
Hardmode Mobs
Some of the new mobs added once you used a Shadow Core.
Shadow Core Holder
It holds the Shadow Core. You can harvest it with an iron pickaxe at least, and then activate Hardmode.
Hardmode Items
A bunch on items added by the mod. That's not all of them though !
Hardmode Ores and Gear
Hardmode ores and gear. You will need a pickaxe stronger than diamond to mine any of them.