This is factorio in a tower defense style scenario. It is faster paced than sandbox mode and the campaign levels and you will be entirely focused on building your defenses and holding off waves. The closest analogon is the wave defense scenario in vanilla, though this one has a few twists on its own. It will take about an hour if you can live through it. The difficulty is somewhere between hard and very hard but not insane. Playing in multiplayer may make things easier.
This is an early version of the scenario that is playable but not entirely polished. Balancing could definitely use work, it's missing a few features and there are still some bugs, the most visible ones are related to biters. Nevertheless I think it is enjoyable in its current state. I would like to add difficulty levels eventually but I'd like to get the one difficulty that exists currently balanced first. At this point I'd like to see feedback on pretty much everything in the scenario.
The scenario makes use of: factorio-stdlib rocket turrets from Predictabowl's Turrets Mod