diff --git a/iris.overworld.swamp/biomes/swamp-mountains.json b/iris.overworld.swamp/biomes/swamp-mountains.json
index ec38d12b..826333f9 100644
--- a/iris.overworld.swamp/biomes/swamp-mountains.json
+++ b/iris.overworld.swamp/biomes/swamp-mountains.json
@@ -24,6 +24,30 @@
             ]
         }
     ],
+    "slab": {
+        "dispersion": "WISPY",
+        "terrainZoom": 0.35,
+        "palette": [
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "minecraft:mossy_cobblestone_slab[type=bottom,waterlogged=false]",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "minecraft:cobblestone_slab[type=bottom,waterlogged=false]",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR"
+        ]
+    },
     "objects": [
         {
             "chance": 2.0,
diff --git a/iris.overworld.swamp/biomes/swamp-oak-denmyre.json b/iris.overworld.swamp/biomes/swamp-oak-denmyre.json
index ddd782e3..9d4fe978 100644
--- a/iris.overworld.swamp/biomes/swamp-oak-denmyre.json
+++ b/iris.overworld.swamp/biomes/swamp-oak-denmyre.json
@@ -36,6 +36,23 @@
             ]
         }
     ],
+    "slab": {
+        "dispersion": "WISPY",
+        "terrainZoom": 0.35,
+        "palette": [
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "minecraft:cobblestone_slab[type=bottom,waterlogged=false]",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR"
+        ]
+    },
     "decorators": [
         {
             "zoom": 0.01,
diff --git a/iris.overworld.swamp/biomes/swamp-roofed.json b/iris.overworld.swamp/biomes/swamp-roofed.json
index d3238908..f2e1a5b4 100644
--- a/iris.overworld.swamp/biomes/swamp-roofed.json
+++ b/iris.overworld.swamp/biomes/swamp-roofed.json
@@ -33,6 +33,30 @@
             ]
         }
     ],
+    "slab": {
+        "dispersion": "WISPY",
+        "terrainZoom": 0.35,
+        "palette": [
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "minecraft:mossy_cobblestone_slab[type=bottom,waterlogged=false]",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "minecraft:cobblestone_slab[type=bottom,waterlogged=false]",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR",
+            "AIR"
+        ]
+    },
     "children": [
         "tundra-mountains"
     ],