Muck Obamium Bar is an item crafted by smelting Obamium Ore in a Furnace. It is used to craft the Night Blade.
Developer Dani added Obamium in Muck update 3 alongside new bosses. With an Adamantite Pickaxe, search for purple rocks called Obamium.
You can find Obamium anywhere including the newly implemented caves. You may only find one or two in there.
You can get Adamantite from green rocks.
First, you need to smell it and turn it into bars. When you have enough Obamium, Black Shard and Dark Oak Wood bars, you will unlock the recipe to make the Night Blade sword. It is one of the best weapons in the game.
You will also need black shards that you can get from the guardians. The dark oak wood can be collected as a Gronk drop and by cutting dark oak trees with an adamantite axe.
You will need exactly 10 Obamium bars, 1 Black Shard and 15 Dark Oak Wood to be able to make the sword on the Anvil.
This metal can also be used on the first shipwreck you find on the ship map in any of the caves. To find a map, look for green chests that usually appear in cabins and wagons.
Once you have the map, go to the wreck to find the option to repair various parts of the ship. You will require some sets of materials, including Obamium for the base of the engine.
However, you will have to fix the ship’s engine located on the deck. You will require 12 iron bars to fix the engine.
You will have to get 5 Obamium bars and other materials to fix the base of the engine.