This mod adds a lategame progression system and very useful items. Enemy spawn rates become dangerous.
(Heavily recommended mods: "Mobs Monster", "Dwarf Fortress style caverns ", "Mesecons", "Hallelujah Mountains (AKA Cloudlands)")
In this mod, Steel Amulets make you mine iron ore directly into steel blocks. There are 5 tiers of steel amulets. They drastically increase how many steel blocks you get while mining, allowing you to build space towers and other megastructures.
There is also a coal amulet. To find recipes, search "amulet" in-game on the recipes menu. Conquer the wild with these resources.
These rewards require Type II Artifacts. These rare resources are the new progression. Get them by mining bright green Megastructure Ore at any level below y=-4. You will need a lot. Also, enemies from Mobs Monster drop them too. Enemies spawn frequently at night, so prepare yourself. Battles will be rewarding.
There are also quality of life recipes. Turn Steel blocks into lots of Glass. You can turn 1 mesecon wire into multiple, avoiding a return trip. Make power plants easily. Type II artifacts fuel these, check your recipe book. Why add these? You can build space elevators with all your steel, and explore the skies above.
Some sky ores are also added, and can be seen if you use the mod "Hallelujah Mountains (AKA Cloudlands)". There is Sky Iron, Rail Ore and Boom Ore (it won't blow up). The latter two give a treasure trove of goodies, but are very rare. You can also find Sky Ore, but its drops do not have a use yet.