diff --git a/core/src/com/unciv/logic/map/TileInfo.kt b/core/src/com/unciv/logic/map/TileInfo.kt
index 4a50ac5d3b..0063427fbb 100644
--- a/core/src/com/unciv/logic/map/TileInfo.kt
+++ b/core/src/com/unciv/logic/map/TileInfo.kt
@@ -483,7 +483,7 @@ open class TileInfo {
             // Tiles with no terrains, and no turns to build, are like great improvements - they're placeable
             improvement.terrainsCanBeBuiltOn.isEmpty() && improvement.turnsToBuild == 0 && isLand -> true
             improvement.terrainsCanBeBuiltOn.contains(topTerrain.name) -> true
-            improvement.uniqueObjects.filter { it.placeholderText == "Must be next to []" }.any {
+            improvement.uniqueObjects.filter { it.type == UniqueType.MustBeNextTo }.any {
                 val filter = it.params[0]
                 if (filter == "River") return@any !isAdjacentToRiver()
                 else return@any !neighbors.any { neighbor -> neighbor.matchesFilter(filter) }
diff --git a/core/src/com/unciv/models/ruleset/Building.kt b/core/src/com/unciv/models/ruleset/Building.kt
index fbedcd79ba..f8edc217e0 100644
--- a/core/src/com/unciv/models/ruleset/Building.kt
+++ b/core/src/com/unciv/models/ruleset/Building.kt
@@ -454,12 +454,12 @@ class Building : RulesetStatsObject(), INonPerpetualConstruction {
         for (unique in uniqueObjects) {
             when (unique.placeholderText) {
                 // Deprecated since 3.16.11, replace with "Not displayed [...] construction without []"
-                    "Not displayed as an available construction unless [] is built" -> 
+                    UniqueType.NotDisplayedUnlessOtherBuildingBuilt.placeholderText ->
                         if (!cityConstructions.containsBuildingOrEquivalent(unique.params[0]))
                             rejectionReasons.add(RejectionReason.ShouldNotBeDisplayed)
                 //
 
-                "Not displayed as an available construction without []" ->
+                UniqueType.NotDisplayedWithout.placeholderText ->
                     if (unique.params[0] in ruleSet.tileResources && !civInfo.hasResource(unique.params[0])
                         || unique.params[0] in ruleSet.buildings && !cityConstructions.containsBuildingOrEquivalent(unique.params[0])
                         || unique.params[0] in ruleSet.technologies && !civInfo.tech.isResearched(unique.params[0])
@@ -470,22 +470,22 @@ class Building : RulesetStatsObject(), INonPerpetualConstruction {
                 "Enables nuclear weapon" -> if (!cityConstructions.cityInfo.civInfo.gameInfo.gameParameters.nuclearWeaponsEnabled) 
                         rejectionReasons.add(RejectionReason.DisabledBySetting)
 
-                "Must be on []" -> 
+                UniqueType.MustBeOn.placeholderText ->
                     if (!cityCenter.matchesTerrainFilter(unique.params[0], civInfo))
                         rejectionReasons.add(RejectionReason.MustBeOnTile.apply { errorMessage = unique.text })
 
-                "Must not be on []" -> 
+                UniqueType.MustNotBeOn.placeholderText ->
                     if (cityCenter.matchesTerrainFilter(unique.params[0], civInfo))
                         rejectionReasons.add(RejectionReason.MustNotBeOnTile.apply { errorMessage = unique.text })
 
-                "Must be next to []" -> 
+                UniqueType.MustBeNextTo.placeholderText ->
                     if (// Fresh water is special, in that rivers are not tiles themselves but also fit the filter.
                         !(unique.params[0] == "Fresh water" && cityCenter.isAdjacentToRiver()) 
                         && cityCenter.getTilesInDistance(1).none { it.matchesFilter(unique.params[0], civInfo) }
                     ) 
                         rejectionReasons.add(RejectionReason.MustBeNextToTile.apply { errorMessage = unique.text })
 
-                "Must not be next to []" -> 
+                UniqueType.MustNotBeNextTo.placeholderText ->
                     if (cityCenter.getTilesInDistance(1).any { it.matchesFilter(unique.params[0], civInfo) }) 
                         rejectionReasons.add(RejectionReason.MustNotBeNextToTile.apply { errorMessage = unique.text })
 
diff --git a/core/src/com/unciv/models/ruleset/unique/UniqueType.kt b/core/src/com/unciv/models/ruleset/unique/UniqueType.kt
index ec8c12b3b3..d596a75311 100644
--- a/core/src/com/unciv/models/ruleset/unique/UniqueType.kt
+++ b/core/src/com/unciv/models/ruleset/unique/UniqueType.kt
@@ -197,6 +197,16 @@ enum class UniqueType(val text:String, vararg targets: UniqueTarget, val flags:
     CannotBeBuiltWith("Cannot be built with [buildingName]", UniqueTarget.Building),
     RequiresAnotherBuilding("Requires a [buildingName] in this city", UniqueTarget.Building),
 
+    NotDisplayedWithout("Not displayed as an available construction without [buildingName/tech/resource/policy]", UniqueTarget.Building, UniqueTarget.Unit),
+    //UniqueType added in 3.18.4
+    @Deprecated("As of 3.16.11", ReplaceWith("Not displayed as an available construction without [buildingName]"), DeprecationLevel.WARNING)
+    NotDisplayedUnlessOtherBuildingBuilt("Not displayed as an available construction unless [buildingName] is built", UniqueTarget.Building),
+
+    MustBeOn("Must be on [terrainFilter]", UniqueTarget.Building),
+    MustNotBeOn("Must not be on [terrainFilter]", UniqueTarget.Building),
+    MustBeNextTo("Must be next to [terrainFilter]", UniqueTarget.Building),
+    MustNotBeNextTo("Must not be next to [terrainFilter]", UniqueTarget.Building),
+
 
     ///////////////////////////////////////// UNIT UNIQUES /////////////////////////////////////////
 
diff --git a/core/src/com/unciv/models/ruleset/unit/BaseUnit.kt b/core/src/com/unciv/models/ruleset/unit/BaseUnit.kt
index 70c9e2d6ab..a932510960 100644
--- a/core/src/com/unciv/models/ruleset/unit/BaseUnit.kt
+++ b/core/src/com/unciv/models/ruleset/unit/BaseUnit.kt
@@ -379,7 +379,7 @@ class BaseUnit : RulesetObject(), INonPerpetualConstruction {
         if (isWaterUnit() && !cityConstructions.cityInfo.isCoastal())
             rejectionReasons.add(RejectionReason.WaterUnitsInCoastalCities)
         val civInfo = cityConstructions.cityInfo.civInfo
-        for (unique in uniqueObjects.filter { it.placeholderText == "Not displayed as an available construction without []" }) {
+        for (unique in uniqueObjects.filter { it.type == UniqueType.NotDisplayedWithout }) {
             val filter = unique.params[0]
             if (filter in civInfo.gameInfo.ruleSet.tileResources && !civInfo.hasResource(filter)
                     || filter in civInfo.gameInfo.ruleSet.buildings && !cityConstructions.containsBuildingOrEquivalent(filter))