diff --git a/assets/mods/basegame/fluid/2.tga b/assets/mods/basegame/fluid/2.tga
index 23132c04a..7ad4afecd 100644
--- a/assets/mods/basegame/fluid/2.tga
+++ b/assets/mods/basegame/fluid/2.tga
@@ -1,3 +1,3 @@
 version https://git-lfs.github.com/spec/v1
-oid sha256:1381c3005e563c2b84d91373393f20560decbda6463eaa7ae3eaadf661e00992
+oid sha256:5dec2701eb9b1fc235f0239f3531f4e7e6a5cdc42f8af7d5bb7919a4629cf221
 size 55314
diff --git a/src/net/torvald/gdx/graphics/Cvec.kt b/src/net/torvald/gdx/graphics/Cvec.kt
index 035b50452..f7681d2c4 100644
--- a/src/net/torvald/gdx/graphics/Cvec.kt
+++ b/src/net/torvald/gdx/graphics/Cvec.kt
@@ -323,11 +323,12 @@ class Cvec {
 
     /** Returns the color encoded as hex string with the format RRGGBBAA.  */
     override fun toString(): String {
-        var value = Integer
+        /*var value = Integer
                 .toHexString((255 * r).toInt() shl 24 or ((255 * g).toInt() shl 16) or ((255 * b).toInt() shl 8) or (255 * a).toInt())
         while (value.length < 8)
             value = "0$value"
-        return value
+        return value*/
+        return "($r,$g,$b,$a)"
     }
 
     /** Sets the RGB Cvec components using the specified Hue-Saturation-Value. Note that HSV components are voluntary not clamped
diff --git a/src/net/torvald/gdx/graphics/UnsafeCvecArray.kt b/src/net/torvald/gdx/graphics/UnsafeCvecArray.kt
index abe7b206b..4711b718f 100644
--- a/src/net/torvald/gdx/graphics/UnsafeCvecArray.kt
+++ b/src/net/torvald/gdx/graphics/UnsafeCvecArray.kt
@@ -53,6 +53,7 @@ internal class UnsafeCvecArray(val width: Int, val height: Int) {
         target.g = array.getFloat(a + 1)
         target.b = array.getFloat(a + 2)
         target.a = array.getFloat(a + 3)
+        checkNaN(target)
     }
     /**
      * `getAndSet(cvec, x, y, func)` is equivalent to
@@ -80,6 +81,7 @@ internal class UnsafeCvecArray(val width: Int, val height: Int) {
 //    fun setA(x: Int, y: Int, value: Float) { array.setFloat(toAddr(x, y) + 3, value) }
 //    operator fun set(i: Long, value: Float) = array.setFloat(i, value)
     fun setVec(x: Int, y: Int, value: Cvec) {
+        checkNaN(value)
         val a = toAddr(x, y)
         array.setFloat(a + 0, value.r)
         array.setFloat(a + 1, value.g)
@@ -87,6 +89,8 @@ internal class UnsafeCvecArray(val width: Int, val height: Int) {
         array.setFloat(a + 3, value.a)
     }
     fun setScalar(x: Int, y: Int, value: Float) {
+        checkNaN(value)
+
         val a = toAddr(x, y)
 
         array.setFloat(a + 0, value)
@@ -103,6 +107,7 @@ internal class UnsafeCvecArray(val width: Int, val height: Int) {
 
     // operators
     fun max(x: Int, y: Int, other: Cvec) {
+        checkNaN(other)
         val a = toAddr(x, y)
         array.setFloat(a + 0, kotlin.math.max(array.getFloat(a + 0), other.r))
         array.setFloat(a + 1, kotlin.math.max(array.getFloat(a + 1), other.g))
@@ -110,6 +115,7 @@ internal class UnsafeCvecArray(val width: Int, val height: Int) {
         array.setFloat(a + 3, kotlin.math.max(array.getFloat(a + 3), other.a))
     }
     fun mul(x: Int, y: Int, scalar: Float) {
+        checkNaN(scalar)
         val a = toAddr(x, y)
         array.setFloat(a + 0, (array.getFloat(a + 0) * scalar))
         array.setFloat(a + 1, (array.getFloat(a + 1) * scalar))
@@ -118,6 +124,7 @@ internal class UnsafeCvecArray(val width: Int, val height: Int) {
     }
 
     fun mulAndAssign(x: Int, y: Int, scalar: Float) {
+        checkNaN(scalar)
         val addr = toAddr(x, y)
         array.setFloat(addr + 0, (array.getFloat(addr + 0) * scalar))
         array.setFloat(addr + 1, (array.getFloat(addr + 1) * scalar))
@@ -141,6 +148,12 @@ internal class UnsafeCvecArray(val width: Int, val height: Int) {
 
     fun destroy() = this.array.destroy()
 
+    private inline fun checkNaN(vec: Cvec) {
+//        if (vec.r.isNaN() || vec.g.isNaN() || vec.b.isNaN() || vec.a.isNaN()) throw Error("Vector contains NaN (${vec.r},${vec.g},${vec.b},${vec.a})")
+    }
+    private inline fun checkNaN(scalar: Float) {
+//        if (scalar.isNaN()) throw Error("Scalar value is NaN ($scalar)")
+    }
 }
 
 
diff --git a/src/net/torvald/terrarum/blockproperties/Fluid.kt b/src/net/torvald/terrarum/blockproperties/Fluid.kt
index 47ddbca1c..77de79262 100644
--- a/src/net/torvald/terrarum/blockproperties/Fluid.kt
+++ b/src/net/torvald/terrarum/blockproperties/Fluid.kt
@@ -11,5 +11,6 @@ object Fluid {
     val NULL = Block.AIR
     val WATER = "fluid@basegame:1"
     val LAVA = "fluid@basegame:2"
+    val CRUDE_OIL = "fluid@basegame:3"
 
 }
\ No newline at end of file
diff --git a/src/net/torvald/terrarum/gameworld/GameWorld.kt b/src/net/torvald/terrarum/gameworld/GameWorld.kt
index 97f9a4f47..2cb0a87cc 100644
--- a/src/net/torvald/terrarum/gameworld/GameWorld.kt
+++ b/src/net/torvald/terrarum/gameworld/GameWorld.kt
@@ -874,7 +874,7 @@ open class GameWorld(
         if (fluidID == Block.NULL || fluidID == Block.NOT_GENERATED)
             fluidID = Fluid.NULL
 
-        return FluidInfo(fluidID, fill.let { if (it.isNaN()) 0f else it }) // hex FFFFFFFF (magic number for ungenerated tiles) is interpreted as Float.NaN
+        return FluidInfo(fluidID, if (fill.isNaN()) 0f else fill) // hex FFFFFFFF (magic number for ungenerated tiles) is interpreted as Float.NaN
     }
 
     /*private fun fluidTypeToBlock(type: FluidType) = when (type.abs()) {
diff --git a/src/net/torvald/terrarum/modulebasegame/gameitems/ItemBottomlessWaterBucket.kt b/src/net/torvald/terrarum/modulebasegame/gameitems/ItemBottomlessWaterBucket.kt
index 81161d6e9..4aec1e13f 100644
--- a/src/net/torvald/terrarum/modulebasegame/gameitems/ItemBottomlessWaterBucket.kt
+++ b/src/net/torvald/terrarum/modulebasegame/gameitems/ItemBottomlessWaterBucket.kt
@@ -61,7 +61,7 @@ class ItemBottomlessLavaBucket(originalID: ItemID) : GameItem(originalID) {
     override fun startPrimaryUse(actor: ActorWithBody, delta: Float): Long {
         val mx = Terrarum.mouseTileX; val my =Terrarum.mouseTileY
         if (!BlockCodex[INGAME.world.getTileFromTerrain(mx, my)].isSolid) {
-            INGAME.world.setFluid(mx, my, Fluid.LAVA, 1f)
+            INGAME.world.setFluid(mx, my, Fluid.CRUDE_OIL, 1f)
             return 0L
         }
         else {
diff --git a/src/net/torvald/terrarum/modulebasegame/worldgenerator/Aquagen.kt b/src/net/torvald/terrarum/modulebasegame/worldgenerator/Aquagen.kt
new file mode 100644
index 000000000..c53e1e57c
--- /dev/null
+++ b/src/net/torvald/terrarum/modulebasegame/worldgenerator/Aquagen.kt
@@ -0,0 +1,266 @@
+package net.torvald.terrarum.modulebasegame.worldgenerator
+
+import com.sudoplay.joise.Joise
+import com.sudoplay.joise.module.*
+import net.torvald.terrarum.BlockCodex
+import net.torvald.terrarum.INGAME
+import net.torvald.terrarum.LoadScreenBase
+import net.torvald.terrarum.blockproperties.Block
+import net.torvald.terrarum.blockproperties.Fluid
+import net.torvald.terrarum.gameitems.isFluid
+import net.torvald.terrarum.gameworld.GameWorld
+import net.torvald.terrarum.realestate.LandUtil.CHUNK_H
+import net.torvald.terrarum.realestate.LandUtil.CHUNK_W
+import kotlin.math.cos
+import kotlin.math.sin
+
+/**
+ * Created by minjaesong on 2024-09-10.
+ */
+class Aquagen(world: GameWorld, isFinal: Boolean, val groundScalingCached: ModuleCache, seed: Long, params: Any) : Gen(world, isFinal, seed, params) {
+
+    private val FLUID_FILL = 1.2f
+
+    override fun getDone(loadscreen: LoadScreenBase?) {
+        loadscreen?.let {
+            it.stageValue += 1
+            it.progress.set(0L)
+        }
+
+        Worldgen.threadExecutor.renew()
+        submitJob(loadscreen)
+        Worldgen.threadExecutor.join()
+    }
+
+    override fun draw(xStart: Int, yStart: Int, noises: List<Joise>, soff: Double) {
+        if (INGAME.worldGenVer != null && INGAME.worldGenVer!! <= 0x0000_000004_000003) return
+
+        for (x in xStart until xStart + CHUNK_W) {
+            val st = (x.toDouble() / world.width) * TWO_PI
+
+            for (y in yStart until yStart + CHUNK_H) {
+                val sx = sin(st) * soff + soff // plus sampleOffset to make only
+                val sz = cos(st) * soff + soff // positive points are to be sampled
+                val sy = Worldgen.getSY(y)
+                // DEBUG NOTE: it is the OFFSET FROM THE IDEAL VALUE (observed land height - (HEIGHT * DIVISOR)) that must be constant
+
+                // get the actual noise values
+                // the size of the two lists are guaranteed to be identical as they all derive from the same `ores`
+                val noiseValues = noises.map { it.get(sx, sy, sz) }
+
+                val lavaVal = noiseValues[noiseValues.lastIndex - 2]
+                val lava = (lavaVal >= 0.5)
+
+                val waterVal = noiseValues[noiseValues.lastIndex - 1]
+                val waterShell = (waterVal >= 0.32)
+                val water = (waterVal >= 0.5)
+
+                val oilVal = noiseValues[noiseValues.lastIndex]
+                val oilShell = (oilVal >= 0.38)
+                val oil = (oilVal >= 0.5)
+
+                val backingTile = world.getTileFromWall(x, y)
+
+                val outFluid = if (water) Fluid.WATER
+                else if (oil) Fluid.CRUDE_OIL
+                else if (lava) Fluid.LAVA
+                else if (waterShell) backingTile
+                else if (oilShell) backingTile
+                else null
+
+                outFluid?.let {
+                    if (outFluid.isFluid()) {
+                        world.setTileTerrain(x, y, Block.AIR, true)
+                        world.setFluid(x, y, outFluid, FLUID_FILL)
+                    }
+                    else {
+                        world.setTileTerrain(x, y, outFluid, true)
+                    }
+                }
+            }
+        }
+    }
+
+
+    override fun getGenerator(seed: Long, params: Any?): List<Joise> {
+        return listOf(
+            Joise(generateSeaOfLava(seed)),
+            Joise(generateAquifer(seed, groundScalingCached)),
+            Joise(generateCrudeOil(seed, groundScalingCached)),
+        )
+    }
+
+    private fun generateSeaOfLava(seed: Long): Module {
+        val params = params as TerragenParams
+
+        val lavaPipe = ModuleScaleDomain().also {
+            it.setSource(ModuleFractal().also {
+                it.setType(ModuleFractal.FractalType.RIDGEMULTI)
+                it.setAllSourceBasisTypes(ModuleBasisFunction.BasisType.GRADIENT)
+                it.setAllSourceInterpolationTypes(ModuleBasisFunction.InterpolationType.QUINTIC)
+                it.setNumOctaves(1)
+                it.setFrequency(params.lavaShapeFreg) // adjust the "density" of the caves
+                it.seed = seed shake "LattiaOnLavaa"
+            })
+            it.setScaleY(1.0 / 6.0)
+        }
+
+
+        val lavaPerturbFractal = ModuleFractal().also {
+            it.setType(ModuleFractal.FractalType.FBM)
+            it.setAllSourceBasisTypes(ModuleBasisFunction.BasisType.GRADIENT)
+            it.setAllSourceInterpolationTypes(ModuleBasisFunction.InterpolationType.QUINTIC)
+            it.setNumOctaves(6)
+            it.setFrequency(params.lavaShapeFreg * 3.0 / 4.0)
+            it.seed = seed shake "FloorIsLava"
+        }
+
+        val lavaPerturbScale = ModuleScaleOffset().also {
+            it.setSource(lavaPerturbFractal)
+            it.setScale(23.0)
+            it.setOffset(0.0)
+        }
+
+        val lavaPerturb = ModuleTranslateDomain().also {
+            it.setSource(lavaPipe)
+            it.setAxisXSource(lavaPerturbScale)
+        }
+
+        val lavaSelect = ModuleSelect().also {
+            it.setLowSource(1.0)
+            it.setHighSource(0.0)
+            it.setControlSource(lavaPerturb)
+            it.setThreshold(lavaGrad)
+            it.setFalloff(0.0)
+        }
+
+
+        return lavaSelect
+    }
+
+    private fun generateAquifer(seed: Long, groundScalingCached: Module): Module {
+        val params = params as TerragenParams
+
+        val waterPocket = ModuleScaleDomain().also {
+            it.setSource(ModuleFractal().also {
+                it.setType(ModuleFractal.FractalType.BILLOW)
+                it.setAllSourceBasisTypes(ModuleBasisFunction.BasisType.SIMPLEX)
+                it.setAllSourceInterpolationTypes(ModuleBasisFunction.InterpolationType.QUINTIC)
+                it.setNumOctaves(4)
+                it.setFrequency(params.rockBandCutoffFreq / params.featureSize)
+                it.seed = seed shake "WaterPocket"
+            })
+            it.setScaleX(0.5)
+            it.setScaleZ(0.5)
+            it.setScaleY(0.8)
+        }
+
+        val terrainBool = ModuleSelect().also {
+            it.setLowSource(0.0)
+            it.setHighSource(1.0)
+            it.setControlSource(groundScalingCached)
+            it.setThreshold(0.5)
+            it.setFalloff(0.1)
+        }
+
+        val aquifer = ModuleCombiner().also {
+            it.setType(ModuleCombiner.CombinerType.MULT)
+            it.setSource(0, waterPocket)
+            it.setSource(1, terrainBool)
+            it.setSource(2, aquiferGrad)
+        }
+
+
+        return aquifer
+    }
+
+    private fun generateCrudeOil(seed: Long, groundScalingCached: Module): Module {
+        val params = params as TerragenParams
+
+        val oilPocket = ModuleScaleDomain().also {
+            it.setSource(ModuleFractal().also {
+                it.setType(ModuleFractal.FractalType.BILLOW)
+                it.setAllSourceBasisTypes(ModuleBasisFunction.BasisType.SIMPLEX)
+                it.setAllSourceInterpolationTypes(ModuleBasisFunction.InterpolationType.QUINTIC)
+                it.setNumOctaves(4)
+                it.setFrequency(params.rockBandCutoffFreq / params.featureSize)
+                it.seed = seed shake "CrudeOil"
+            })
+            it.setScaleX(0.16)
+            it.setScaleZ(0.16)
+            it.setScaleY(1.4)
+        }
+
+        crudeOilGradStart = TerrarumModuleCacheY().also {
+            it.setSource(ModuleClamp().also {
+                it.setSource(ModuleScaleOffset().also {
+                    it.setSource(groundScalingCached)
+                    it.setOffset(-8.0)
+                })
+                it.setRange(0.0, 1.0)
+            })
+        }
+
+        crudeOilGrad = TerrarumModuleCacheY().also {
+            it.setSource(ModuleCombiner().also {
+                it.setType(ModuleCombiner.CombinerType.ADD)
+                it.setSource(0, crudeOilGradStart)
+                it.setSource(1, crudeOilGradEnd)
+                it.setSource(2, ModuleConstant().also { it.setConstant(-1.0) })
+            })
+        }
+
+        val oilLayer = ModuleCombiner().also {
+            it.setType(ModuleCombiner.CombinerType.MULT)
+            it.setSource(0, oilPocket)
+            it.setSource(1, crudeOilGrad)
+        }
+
+
+        return oilLayer
+    }
+
+    companion object {
+
+        // val = sqrt((y-H+L) / L); where H=5300 (world height-100), L=620;
+        // 100 is the height of the "base lava sheet", 600 is the height of the "transitional layer"
+        // in this setup, the entire lava layer never exceeds 8 chunks (720 tiles) in height
+        val lavaGrad = TerrarumModuleCacheY().also {
+            it.setSource(TerrarumModuleLavaFloorGrad().also {
+                it.setH(5300.0)
+                it.setL(620.0)
+            })
+        }
+
+        val aquiferGrad = TerrarumModuleCacheY().also {
+            it.setSource(TerrarumModuleCaveLayerClosureGrad().also {
+                it.setH(4300.0)
+                it.setL(620.0)
+            })
+        }
+
+        lateinit var crudeOilGradStart: TerrarumModuleCacheY
+        lateinit var crudeOilGrad: TerrarumModuleCacheY
+
+        val crudeOilGradEnd = TerrarumModuleCacheY().also {
+            it.setSource(TerrarumModuleCaveLayerClosureGrad().also {
+                it.setH(4800.0)
+                it.setL(620.0)
+            })
+        }
+
+        val caveTerminalClosureGrad = TerrarumModuleCacheY().also {
+            it.setSource(TerrarumModuleCaveLayerClosureGrad().also {
+                it.setH(17.2)
+                it.setL(3.0)
+            })
+        }
+        val aquiferTerminalClosureGrad = TerrarumModuleCacheY().also {
+            it.setSource(TerrarumModuleCaveLayerClosureGrad().also {
+                it.setH(21.0)
+                it.setL(8.0)
+            })
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/src/net/torvald/terrarum/modulebasegame/worldgenerator/Cavegen.kt b/src/net/torvald/terrarum/modulebasegame/worldgenerator/Cavegen.kt
index f86730401..1b5d5d965 100644
--- a/src/net/torvald/terrarum/modulebasegame/worldgenerator/Cavegen.kt
+++ b/src/net/torvald/terrarum/modulebasegame/worldgenerator/Cavegen.kt
@@ -2,6 +2,7 @@ package net.torvald.terrarum.modulebasegame.worldgenerator
 
 import com.sudoplay.joise.Joise
 import com.sudoplay.joise.module.*
+import net.torvald.terrarum.INGAME
 import net.torvald.terrarum.LoadScreenBase
 import net.torvald.terrarum.blockproperties.Block
 import net.torvald.terrarum.gameworld.GameWorld
@@ -99,11 +100,19 @@ class Cavegen(world: GameWorld, isFinal: Boolean, val highlandLowlandSelectCache
             it.setOffset(0.0)
         }
 
-        val cavePerturb = ModuleTranslateDomain().also {
+        val cavePerturb0 = ModuleTranslateDomain().also {
             it.setSource(caveShapeAttenuate)
             it.setAxisXSource(cavePerturbScale)
         }
 
+        val cavePerturb = ModuleCombiner().also { // 0: rock, 1: air
+            it.setType(ModuleCombiner.CombinerType.MULT)
+            it.setSource(0, cavePerturb0)
+            // basically disabling terminal closure for the world generated from the old version
+            if (INGAME.worldGenVer != null && INGAME.worldGenVer!! <= 0x0000_000004_000003)
+                it.setSource(1, caveTerminalClosureGrad)
+        }
+
         val caveSelect = ModuleSelect().also {
             it.setLowSource(1.0)
             it.setHighSource(0.0)
@@ -161,4 +170,13 @@ class Cavegen(world: GameWorld, isFinal: Boolean, val highlandLowlandSelectCache
             Joise(caveScaling)
         )
     }
+
+    companion object {
+        val caveTerminalClosureGrad = TerrarumModuleCacheY().also {
+            it.setSource(TerrarumModuleCaveLayerClosureGrad().also {
+                it.setH(17.2)
+                it.setL(3.0)
+            })
+        }
+    }
 }
\ No newline at end of file
diff --git a/src/net/torvald/terrarum/modulebasegame/worldgenerator/Terragen.kt b/src/net/torvald/terrarum/modulebasegame/worldgenerator/Terragen.kt
index 57222f141..bb889edce 100644
--- a/src/net/torvald/terrarum/modulebasegame/worldgenerator/Terragen.kt
+++ b/src/net/torvald/terrarum/modulebasegame/worldgenerator/Terragen.kt
@@ -16,7 +16,7 @@ import kotlin.math.sin
 /**
  * Created by minjaesong on 2019-07-23.
  */
-class Terragen(world: GameWorld, isFinal: Boolean , val highlandLowlandSelectCache: ModuleCache, seed: Long, params: Any) : Gen(world, isFinal, seed, params) {
+class Terragen(world: GameWorld, isFinal: Boolean, val groundScalingCached: ModuleCache, seed: Long, params: Any) : Gen(world, isFinal, seed, params) {
 
     private val dirtStoneDitherSize = 3 // actual dither size will be double of this value
     private val stoneSlateDitherSize = 4
@@ -151,24 +151,12 @@ class Terragen(world: GameWorld, isFinal: Boolean , val highlandLowlandSelectCac
         // they should be treated properly when you actually generate the world out of the noisemap
         // for the visualisation, no treatment will be done in this demo app.
 
-        val groundClamp = ModuleClamp().also {
-            it.setRange(0.0, 100.0)
-            it.setSource(highlandLowlandSelectCache)
-        }
-
-        val groundScaling = ModuleScaleDomain().also {
-            it.setScaleX(1.0 / params.featureSize) // adjust this value to change features size
-            it.setScaleY(1.0 / params.featureSize)
-            it.setScaleZ(1.0 / params.featureSize)
-            it.setSource(groundClamp)
-        }
-
         val marblerng = HQRNG(seed) // this must be here: every slice must get identical series of random numbers
 
         return listOf(
-            Joise(groundScaling),
+            Joise(groundScalingCached),
 
-            Joise(generateRockLayer(groundScaling, seed, params, (0..7).map {
+            Joise(generateRockLayer(groundScalingCached, seed, params, (0..7).map {
                 thicknesses[it] + marblerng.nextTriangularBal() * 0.006 to (1.04 * params.terragenTiers[3] * terragenYscaling) + it * 0.18 + marblerng.nextTriangularBal() * 0.09
             })),
         )
diff --git a/src/net/torvald/terrarum/modulebasegame/worldgenerator/Worldgen.kt b/src/net/torvald/terrarum/modulebasegame/worldgenerator/Worldgen.kt
index 3ce04524a..9bacf390b 100644
--- a/src/net/torvald/terrarum/modulebasegame/worldgenerator/Worldgen.kt
+++ b/src/net/torvald/terrarum/modulebasegame/worldgenerator/Worldgen.kt
@@ -59,12 +59,14 @@ object Worldgen {
         params = genParams
 
         highlandLowlandSelectCache = getHighlandLowlandSelectCache(params.terragenParams, params.seed)
-        caveAttenuateBiasScaledCache = getCaveAttenuateBiasScaled(highlandLowlandSelectCache, params.terragenParams)
+        caveAttenuateBiasScaledForOresCache = getCaveAttenuateBiasScaled(highlandLowlandSelectCache, params.terragenParams)
+        groundScalingCached = getGroundScalingCached(highlandLowlandSelectCache, params.terragenParams)
         biomeMap = HashMap()
     }
 
+    internal lateinit var groundScalingCached: ModuleCache
     internal lateinit var highlandLowlandSelectCache: ModuleCache
-    internal lateinit var caveAttenuateBiasScaledCache: ModuleCache
+    internal lateinit var caveAttenuateBiasScaledForOresCache: ModuleCache
     internal lateinit var biomeMap: HashMap<BlockAddress, Byte>
 
 
@@ -86,11 +88,12 @@ object Worldgen {
         else { work: Work -> (work.tags union tags).isNotEmpty() }
 
         return listOf(
-            Work(Lang["MENU_IO_WORLDGEN_RETICULATING_SPLINES"], Terragen(world, false, highlandLowlandSelectCache, params.seed, params.terragenParams), listOf("TERRAIN")), // also generates marble veins
-            Work(Lang["MENU_IO_WORLDGEN_GROWING_MINERALS"], Oregen(world, false, caveAttenuateBiasScaledCache, params.seed, oreRegistry), listOf("ORES")),
+            Work(Lang["MENU_IO_WORLDGEN_RETICULATING_SPLINES"], Terragen(world, false, groundScalingCached, params.seed, params.terragenParams), listOf("TERRAIN")), // also generates marble veins
+            Work(Lang["MENU_IO_WORLDGEN_CARVING_EARTH"], Cavegen(world, false, highlandLowlandSelectCache, params.seed, params.terragenParams), listOf("TERRAIN", "CAVE")),
+            Work(Lang["MENU_IO_WORLDGEN_FLOODING_UNDERGROUND"], Aquagen(world, false, groundScalingCached, params.seed, params.terragenParams), listOf("WATER")),
+            Work(Lang["MENU_IO_WORLDGEN_GROWING_MINERALS"], Oregen(world, false, caveAttenuateBiasScaledForOresCache, params.seed, oreRegistry), listOf("ORES")),
             Work(Lang["MENU_IO_WORLDGEN_POSITIONING_ROCKS"], OregenAutotiling(world, false, params.seed, oreTilingModes), listOf("ORES")),
             // TODO generate gemstones
-            Work(Lang["MENU_IO_WORLDGEN_CARVING_EARTH"], Cavegen(world, false, highlandLowlandSelectCache, params.seed, params.terragenParams), listOf("TERRAIN", "CAVE")),
             Work(Lang["MENU_IO_WORLDGEN_PAINTING_GREEN"], Biomegen(world, false, params.seed, params.biomegenParams, biomeMap), listOf("BIOME")),
             Work(Lang["MENU_IO_WORLDGEN_PAINTING_GREEN"], Treegen(world, true, params.seed, params.terragenParams, params.treegenParams, biomeMap), listOf("TREES")),
         ).filter(tagFilter)
@@ -454,6 +457,24 @@ object Worldgen {
         }
     }
 
+    private fun getGroundScalingCached(highlandLowlandSelectCache: ModuleCache, params: TerragenParams): ModuleCache {
+        val groundClamp = ModuleClamp().also {
+            it.setRange(0.0, 100.0)
+            it.setSource(highlandLowlandSelectCache)
+        }
+
+        val groundScaling = ModuleScaleDomain().also {
+            it.setScaleX(1.0 / params.featureSize) // adjust this value to change features size
+            it.setScaleY(1.0 / params.featureSize)
+            it.setScaleZ(1.0 / params.featureSize)
+            it.setSource(groundClamp)
+        }
+
+        return ModuleCache().also {
+            it.setSource(groundScaling)
+        }
+    }
+
 }
 
 abstract class Gen(val world: GameWorld, val isFinal: Boolean, val seed: Long, val params: Any? = null) {
diff --git a/src/net/torvald/terrarum/tests/WorldgenNoiseSandbox.kt b/src/net/torvald/terrarum/tests/WorldgenNoiseSandbox.kt
index 66e9b29ae..ffad184d4 100644
--- a/src/net/torvald/terrarum/tests/WorldgenNoiseSandbox.kt
+++ b/src/net/torvald/terrarum/tests/WorldgenNoiseSandbox.kt
@@ -744,7 +744,7 @@ internal class TerragenTest(val params: TerragenParams) : NoiseMaker {
             it.setFalloff(0.0)
         }
 
-        val caveBlockageFractal0 = ModuleFractal().also {
+        val caveBlockageFractal = ModuleFractal().also {
             it.setType(ModuleFractal.FractalType.RIDGEMULTI)
             it.setAllSourceBasisTypes(ModuleBasisFunction.BasisType.GRADIENT)
             it.setAllSourceInterpolationTypes(ModuleBasisFunction.InterpolationType.QUINTIC)
@@ -753,11 +753,6 @@ internal class TerragenTest(val params: TerragenParams) : NoiseMaker {
             it.seed = seed shake caveBlockageMagic
         }
 
-        val caveBlockageFractal = ModuleCombiner().also { // 0: air, 1: rock
-            it.setType(ModuleCombiner.CombinerType.MULT)
-            it.setSource(0, caveBlockageFractal0)
-        }
-
         // will only close-up deeper caves. Shallow caves will be less likely to be closed up
         val caveBlockageAttenuate = ModuleCombiner().also {
             it.setType(ModuleCombiner.CombinerType.MULT)
diff --git a/src/net/torvald/terrarum/worlddrawer/LightmapRenderer.kt b/src/net/torvald/terrarum/worlddrawer/LightmapRenderer.kt
index 8ce9f3c13..1fcc13094 100644
--- a/src/net/torvald/terrarum/worlddrawer/LightmapRenderer.kt
+++ b/src/net/torvald/terrarum/worlddrawer/LightmapRenderer.kt
@@ -538,14 +538,12 @@ object LightmapRenderer {
         }*/
 
         if (_thisFluid.type != Fluid.NULL) {
-            _thisFluid.amount.coerceAtMost(1f).let {
-                _fluidAmountToCol.set(it, it, it, it)
-            }
+            val fluidAmount = _thisFluid.amount.coerceIn(0f, 1f)
 
             _thisTileLuminosity.set(_thisTerrainProp.getLumCol(worldX, worldY))
-            _thisTileLuminosity.maxAndAssign(_thisFluidProp.lumCol.mul(_fluidAmountToCol))
+            _thisTileLuminosity.maxAndAssign(_thisFluidProp.lumCol.cpy().mul(fluidAmount))
             _mapThisTileOpacity.setVec(lx, ly, _thisTerrainProp.opacity)
-            _mapThisTileOpacity.max(lx, ly, _thisFluidProp.opacity.mul(_fluidAmountToCol))
+            _mapThisTileOpacity.max(lx, ly, _thisFluidProp.opacity.cpy().mul(fluidAmount))
         }
         else {
             _thisTileLuminosity.set(_thisTerrainProp.getLumCol(worldX, worldY))
@@ -569,9 +567,8 @@ object LightmapRenderer {
         }
 
         // blend lantern
-        _mapLightLevelThis.max(lx, ly, _thisTileLuminosity.maxAndAssign(
-                lanternMap[LandUtil.getBlockAddr(world, worldX, worldY)] ?: colourNull
-        ))
+        _mapLightLevelThis.max(lx, ly, _thisTileLuminosity)
+        _mapLightLevelThis.max(lx, ly, lanternMap[LandUtil.getBlockAddr(world, worldX, worldY)] ?: colourNull)
     }
 
     private fun precalculate2(lightmap: UnsafeCvecArray, rawx: Int, rawy: Int) {
@@ -698,6 +695,8 @@ object LightmapRenderer {
 //                        val uvlwg = (uvl.sqrt() - 1f) * (1f / 1279f)
 //                        val uvlwb = (uvl.sqrt() - 1f) * (1f / 319f)
 
+                        if (red.isNaN() || grn.isNaN() || blu.isNaN() || uvl.isNaN()) throw IllegalArgumentException("Light vector contains NaN ($red,$grn,$blu,$uvl)")
+
                         if (solidMultMagic == null)
                             lightBuffer.drawPixel(
                                 x - this_x_start,
@@ -867,6 +866,8 @@ object LightmapRenderer {
      * @return -0.5..0.5
      */
     private fun clipfun0(x0: Float): Float {
+        if (x0.isNaN()) throw IllegalArgumentException("Cannot clip NaN value.")
+
         val x = x0 * (1.0f + clip_p1) / 2.0f
         val t = 0.5f * clip_p1