A group of planets still orbiting their dead star.
Mods introducing new content into the game.
New places to build more factories.
Transportation of the player, be it vehicles or teleporters.
Augmented or new ways of transporting materials - belts, inserters, pipes!
New ways to deal with enemies, be it attack or defense.
Armors or armor equipment.
Changes to enemies or entirely new enemies to deal with.
Map generation and terrain modification.
New Ores and resources as well as machines.
Things related to oil and other fluids.
Related to roboports and logistic robots.
Furnaces, assembling machines, production chains.
Changes to power production and distribution.
When I'm placing a Legendary Gas Collector on DeaDia it wont built space platform around itself. Normal quality ones function just fine.
The collector has no interaction with quality, beyond the interactions of a normal roboport. Would be good to know the entity that is there after placement.