Factorio Forums

After the 15.0 update, I found myself with zero incentive to fight the aliens. Settings can make it next to impossible to even run into them until your factory gets to be massive. It would be pretty cool if alien bases dropped crafting materials for a dope weapon, boost rail tracks , sticky grenades, armor, large inventory bags, paint, etc. This would also be pretty cool for servers than run an economy, allowing a faction to specialize in military and fighting alien bases, selling those crafting materials to the economy. Other factions can benefit from this since those materials could be used for other recipes.

On "Default" Settings, Biters grow to encompass broad swathes of the game world past ~4-5 hours and still present a challenge; opposition to expansion and excessive pollution.

It has been noted however that if you try the 'Rail World' settings, the biter density is even sparser and also have their expansion disabled, which may be the problem you are having.

Install bob's mods. not only does my enemies mod add the entities back in, but warfare mod uses them to make weapons!

though, you do kind of need the still currently unreleased tech mod to use them in science packs.