Quantum Shift

System Apocalypse with focus on “realistic” response.

If you've read Shadow Sun, this series is exactly the same but better.

So imo you have 2 routes with System Apocalypse. You've got Primal Hunter/DOTF with a focus on grinding/leveling/loot,... and you have Phase Shift/Shadow Sun/Dawn Of The Void where they focus on structurally dealing with the apocalypse with guns/military/politics.

Phase Shift is strongly in group 2. The story revolves around our MC and his group slowly retaking the US. They take cities, build a military,... They get stronger but it's not really the focus.

The entire series is consistently well written, but overstays its welcome. The first time our MC retakes a major city is pretty cool, the 8th time around it's hard to get excited.

Side note: The retro cover art for this is terrible and kept this on my backlog for a long time