diff --git a/half-earth/scripts/EnvironmentSystem.cs b/half-earth/scripts/EnvironmentSystem.cs
index 758b231..16895ed 100644
--- a/half-earth/scripts/EnvironmentSystem.cs
+++ b/half-earth/scripts/EnvironmentSystem.cs
@@ -55,13 +55,50 @@ public class EnvironmentSystem
         if (!(tile.type is IDamageable damageable))
             return;
 
-        var surplus = tile.temperature - damageable.Threshold;
-        if (surplus < 0)
-            return;
+        var delta = tile.temperature - damageable.Threshold;
+        if (delta < 0)
+        {
+            // we want to heal based on how many wild tiles surround us
+            float healRate = 0.01f;
 
-        // TODO: parameterised balancing
-        tile.currentHealth -= surplus;
-        tile.currentHealth = Mathf.Clamp(tile.currentHealth, 0, 1);
+            // count neighbours
+        }
+        else
+        {
+            // take damage
+            // TODO: parameterised balancing
+            tile.currentHealth -= delta;
+            tile.currentHealth = Mathf.Clamp(tile.currentHealth, 0, 1);
+        }
+
+    }
+
+    public int GetNeighbourCount<T>(int x, int y) where T : TileType
+    {
+        int count = 0;
+
+        for (int i = -1; i < 1; i += 2)
+        {
+            for (int j = -1; j < 1; j += 2)
+            {
+                int xi = x + 1;
+                int yj = y + 1;
+
+                // assume tiles out side of bounds are the same type as this one
+                if (!_tiles.IsInBounds(xi, yj))
+                {
+                    count += 1;
+                    continue;
+                }
+
+                if (!(_tiles[xi, yj] is T))
+                    continue;
+
+                count++;
+            }
+        }
+
+        return count;
     }
 
     private void Diffuse()