Auto Bulldozer — Cities: Skylines II mod

Automatically demolishes abandoned, condemned, and destroyed buildings. Each category is toggleable in Options → Mods → Auto Bulldozer, with a master switch, a configurable grace period for abandoned buildings, an adjustable sweep frequency, and per-category session demolition counters (with a reset button).

Prerequisites (one-time)

1. Windows with Cities: Skylines II installed.
2. Visual Studio 2022 (free Community edition works) with the ".NET desktop development" workload.
3. Install the CS2 modding toolchain: launch the game, go to Options → Modding (or via the Paradox launcher's game settings) and download/install all modding toolsets. This sets the CSII_TOOLPATH environment variable that this project's .csproj relies on. Restart Visual Studio afterwards so it picks up the variable.

Build

Either run .\build.ps1 from the project folder (needs only the .NET SDK — no Visual Studio; the script sets DOTNET_ROLL_FORWARD=LatestMajor because the toolchain's post-processor targets .NET 6), or:

1. Open AutoBulldozer.sln in Visual Studio.
2. Set configuration to Release and build (Ctrl+Shift+B).

Either way, the toolchain automatically copies the built mod to %USERPROFILE%\AppData\LocalLow\Colossal Order\Cities Skylines II\Mods\AutoBulldozer\.

If the build fails with missing references or import errors, CSII_TOOLPATH isn't set — redo step 3 of the prerequisites.

Test in-game

1. Launch CS2 and load a city (or start one).
2. Check Options → Mods → Auto Bulldozer — you should see the toggles.
3. Let the simulation run. Abandoned buildings are cleared a few times per in-game day. The log is at %USERPROFILE%\AppData\LocalLow\Colossal Order\Cities Skylines II\Logs\AutoBulldozer.log.

Publish to Paradox Mods (PDX Mods)

1. Add a thumbnail: place a square PNG (at least 256×256) at Properties/Thumbnail.png. Optionally add screenshots and reference them in Properties/PublishConfiguration.xml.
2. Review Properties/PublishConfiguration.xml — display name, descriptions, tags, version.
3. In Visual Studio, right-click the AutoBulldozer project → the toolchain adds publish options (Publish New Mod). You'll be asked to log in with your Paradox account the first time.
4. After the first publish, the toolchain writes your ModId into PublishConfiguration.xml. Keep it — future updates use Publish New Version (bump ModVersion and update ChangeLog first).
5. Your mod appears at https://mods.paradoxplaza.com/games/cities_skylines_2 under your Paradox account.

How it works

AutoBulldozerSystem is an ECS system that runs during the simulation phase (1–64 sweeps per in-game day, configurable, default 16; no cost while paused or in menus). It queries buildings tagged Abandoned, Condemned, or Destroyed (excluding temporary tool previews and already-deleted entities) and adds the game's Deleted component, letting the vanilla deletion pipeline tear them down cleanly — sub-buildings, renters, and network connections included. Because it only adds a vanilla component, it's save-safe and can be added or removed from a save at any time.

Destroyed buildings are handled more conservatively: only zoned growables (residential/commercial/industrial/office, identified by SpawnableBuildingData on their prefab) are cleared, since the game regrows a building on the freed zone cells. Service buildings, signature buildings, and anything the player placed by hand are skipped, so the option can never delete a service the player would otherwise rebuild.

The optional grace period delays demolition of abandoned buildings by N in-game days, read from the game's own Abandoned.m_AbandonmentTime timestamp — so it's exact and survives saving/loading. Note that vanilla CS2 (DestroyAbandonedSystem) eventually collapses long-abandoned buildings on its own, so a very long grace period may see the building collapse into rubble before the mod demolishes it.

Files

• Mod.cs — entry point (IMod): loads settings, registers options UI and locale, schedules the system
• Setting.cs — options UI definition and persisted settings
• LocaleEN.cs — English strings for the options UI
• AutoBulldozerSystem.cs — the actual demolition logic
• Properties/PublishConfiguration.xml — PDX Mods listing metadata