diff --git a/Tools/Scripts/MapGenerator.cs b/Tools/Scripts/MapGenerator.cs
index a281436..7f721b9 100644
--- a/Tools/Scripts/MapGenerator.cs
+++ b/Tools/Scripts/MapGenerator.cs
@@ -1010,12 +1010,20 @@ public partial class MapGenerator : TextureRect
 			if (t < minTemp || t > maxTemp) continue;
 
 			float centerH = _heightMap[rx, ry];
-			// Sample slope a bit wider (10px) due to higher resolution
+			// Sample slope a bit wider (10px) due to higher resolution.
+			// Samples are clamped to map bounds (task 05): candidates spawn at
+			// [20, MapSize-20] but slopeRadius is 40 at 8K, so the unclamped reads
+			// were out of bounds near the border — previously unreachable only
+			// because border land stayed underwater and failed the sea test first.
 			int slopeRadius = (int)(MapSize * 0.005f); // Automatically scales!
-			if (Mathf.Abs(_heightMap[rx+slopeRadius, ry] - centerH) > maxSlope) continue;
-			if (Mathf.Abs(_heightMap[rx-slopeRadius, ry] - centerH) > maxSlope) continue;
-			if (Mathf.Abs(_heightMap[rx, ry+slopeRadius] - centerH) > maxSlope) continue;
-			if (Mathf.Abs(_heightMap[rx, ry-slopeRadius] - centerH) > maxSlope) continue;
+			int sxHi = Mathf.Clamp(rx + slopeRadius, 0, MapSize - 1);
+			int sxLo = Mathf.Clamp(rx - slopeRadius, 0, MapSize - 1);
+			int syHi = Mathf.Clamp(ry + slopeRadius, 0, MapSize - 1);
+			int syLo = Mathf.Clamp(ry - slopeRadius, 0, MapSize - 1);
+			if (Mathf.Abs(_heightMap[sxHi, ry] - centerH) > maxSlope) continue;
+			if (Mathf.Abs(_heightMap[sxLo, ry] - centerH) > maxSlope) continue;
+			if (Mathf.Abs(_heightMap[rx, syHi] - centerH) > maxSlope) continue;
+			if (Mathf.Abs(_heightMap[rx, syLo] - centerH) > maxSlope) continue;
 
 			bool nearTrueOcean = false;
 			bool nearAnyWater = false;