https://store.steampowered.com/app/644930/They_Are_Billions/
It's easy to deal with a few zombies, since they're very slow and stupid, but as you get more and more of them all over the place, and then huge swarming waves of them, it's insanely challenging!
I love this game, but it's incredibly difficult, even on the easiest setting.
They Are Billions Gameplay - Zombie Defense Post Apocalyptic City Building
https://www.youtube.com/watch?v=DmVx_OMojSY&ab_channel=Splat...
It's fun to use cheats and sandbox mode to play around with the swarming simulation in extreme situations:
1 TRILLION ZOMBIES - They Are Billions
https://www.youtube.com/watch?v=xeczMg3lMdQ&ab_channel=Sergi...
Check out the dynamics of how the waves of different kinds of zombies interact:
It unleashes and mixes layers of different kinds of zombies with different abilities and attacks. (@ 43:00)
The lighter ranged spell casting zombies are maintaining a distance, but then holes form in their layer, and phalanxes of darker hand-to-hand melee zombies squirt through and fill in the gap. (@ 45:00)
At 1:18:30 he admits that it's obvious the zombie waves will never end, so he lets them win!
It reminds me of slime mold hunting an oat flake.
https://www.youtube.com/watch?v=elqwn7k2Wwk&ab_channel=Journ...
I'd love to play SimSlimeMold.
Than Skyrim, easily. Crowd mechanics in Witcher/Cyberpunk give me a pause, but still probably more complex than those.
Popular "simulation" games like Factorio, Rimworld, Dwarf Fortress and Kerbal Space Program are deceptively heavy.