TerrariaMod is a mod that attempts to port over as much content from the game Terraria into Minecraft, while keeping major changes configurable and modpack compatible. It adds several new things from the game including items, tools, and a few bosses.
Join the Terrariamod discord to see development progress and participate in polls for the mod here https://discord.gg/37rqPbU, and check my YouTube channel out for development previews here https://www.youtube.com/channel/UCIuLP8cttaRiArgewiclpiw.