diff --git a/android/assets/jsons/translations/template.properties b/android/assets/jsons/translations/template.properties
index 5372409f2b..8e900cb5a6 100644
--- a/android/assets/jsons/translations/template.properties
+++ b/android/assets/jsons/translations/template.properties
@@ -448,6 +448,8 @@ Clearing a [forest] has created [amount] Production for [cityName] =
 [civName] assigned you a new quest: [questName]. = 
 [civName] rewarded you with [influence] influence for completing the [questName] quest. = 
 The resistance in [cityName] has ended! = 
+Our [name] took [tileDamage] tile damage and was destroyed = 
+Our [name] took [tileDamage] tile damage = 
 
 # World Screen UI
 
diff --git a/core/src/com/unciv/logic/map/MapUnit.kt b/core/src/com/unciv/logic/map/MapUnit.kt
index fb45e7050c..09e3ce833b 100644
--- a/core/src/com/unciv/logic/map/MapUnit.kt
+++ b/core/src/com/unciv/logic/map/MapUnit.kt
@@ -31,6 +31,8 @@ class MapUnit {
     // a major component of getDistanceToTilesWithinTurn,
     // which in turn is a component of getShortestPath and canReach
     @Transient var ignoresTerrainCost = false
+    @Transient var allTilesCosts1 = false
+    @Transient var canPassThroughImpassableTiles = false
     @Transient var roughTerrainPenalty = false
     @Transient var doubleMovementInCoast = false
     @Transient var doubleMovementInForestAndJungle = false
@@ -121,6 +123,8 @@ class MapUnit {
 
         tempUniques = uniques
 
+        allTilesCosts1 = hasUnique("All tiles costs 1")
+        canPassThroughImpassableTiles = hasUnique("Can pass through impassable tiles")
         ignoresTerrainCost = hasUnique("Ignores terrain cost")
         roughTerrainPenalty = hasUnique("Rough terrain penalty")
         doubleMovementInCoast = hasUnique("Double movement in coast")
@@ -439,6 +443,7 @@ class MapUnit {
             }
 
         getCitadelDamage()
+        getTerrainDamage()
     }
 
     fun startTurn() {
@@ -657,6 +662,20 @@ class MapUnit {
                 .sumBy { it.params[0].toInt() }
     }
 
+    private fun getTerrainDamage() {
+        // hard coded mountain damage for now
+        if (getTile().baseTerrain == Constants.mountain) {
+            val tileDamage = 50
+            health -= tileDamage
+
+            if (health <= 0) {
+                civInfo.addNotification("Our [$name] took [$tileDamage] tile damage and was destroyed", currentTile.position, Color.RED)
+                destroy()
+            } else civInfo.addNotification("Our [$name] took [$tileDamage] tile damage", currentTile.position, Color.RED)
+        }
+
+    }
+
     private fun getCitadelDamage() {
         // Check for Citadel damage
         val applyCitadelDamage = currentTile.neighbors
diff --git a/core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt b/core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt
index 6769d5ab95..d517f147c5 100644
--- a/core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt
+++ b/core/src/com/unciv/logic/map/UnitMovementAlgorithms.kt
@@ -8,6 +8,8 @@ class UnitMovementAlgorithms(val unit:MapUnit) {
 
     // This function is called ALL THE TIME and should be as time-optimal as possible!
     fun getMovementCostBetweenAdjacentTiles(from: TileInfo, to: TileInfo, civInfo: CivilizationInfo): Float {
+        if (unit.allTilesCosts1)
+            return 1f
 
         if ((from.isLand != to.isLand) && !unit.civInfo.nation.embarkDisembarkCosts1 && unit.type.isLandUnit())
             return 100f // this is embarkment or disembarkment, and will take the entire turn
@@ -330,8 +332,9 @@ class UnitMovementAlgorithms(val unit:MapUnit) {
     // because optimization on this function results in massive benefits!
     fun canPassThrough(tile: TileInfo): Boolean {
         if (tile.isImpassible()){
-            // special exception - ice tiles are technically impassible, but somme units can move through them anyway
-            if (!(tile.terrainFeature == Constants.ice && unit.canEnterIceTiles))
+            // special exception - ice tiles are technically impassible, but some units can move through them anyway
+            // helicopters can pass through impassable tiles like mountains
+            if (!(tile.terrainFeature == Constants.ice && unit.canEnterIceTiles) && !unit.canPassThroughImpassableTiles)
                 return false
         }
         if (tile.isLand