He adds a Salyum ore to the game. With this ore, you can make armor, 1 food, a fuel (4 times more powerful than coal), some uncraftable spawn eggs and mob spawner.
This ore is harder to find as it is stronger than diamond. Can be found on floors 0 to 20.
In future updates, 1 biom, 1 mob and new version will be added.
The Salyum Mod Team
