building gets xp from working and level up
Mods introducing new content into the game.
New ways to deal with enemies, be it attack or defense.
New Ores and resources as well as machines.
Furnaces, assembling machines, production chains.
Message when fuel processor levels up is somewhat wrong. https://imgur.com/a/92tkF3r
In your settings add 'fuel-processor' to the skipped entities. I believe SE modifies the productivity to give the bonus to the fuel.
