diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/Starbound.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/Starbound.kt
index 835b98f6..997026f1 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/Starbound.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/Starbound.kt
@@ -223,7 +223,7 @@ class Starbound : ISBFileLocator {
 		registerTypeAdapterFactory(InventoryIcon.Factory(pathStack))
 
 		registerTypeAdapterFactory(IArmorItemDefinition.Frames.Factory)
-		registerTypeAdapterFactory(DirectAssetReferenceFactory(pathStack))
+		registerTypeAdapterFactory(AssetPathFactory(pathStack))
 		registerTypeAdapterFactory(ImageReference.Factory({ atlasRegistry.get(it) }, pathStack))
 
 		registerTypeAdapterFactory(AssetReferenceFactory(pathStack, this@Starbound))
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/DirectAssetReference.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/AssetPath.kt
similarity index 63%
rename from src/main/kotlin/ru/dbotthepony/kstarbound/defs/DirectAssetReference.kt
rename to src/main/kotlin/ru/dbotthepony/kstarbound/defs/AssetPath.kt
index 54db63f9..ec26dd6b 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/DirectAssetReference.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/AssetPath.kt
@@ -11,25 +11,25 @@ import ru.dbotthepony.kstarbound.util.PathStack
 /**
  * Путь как указан в JSON + Абсолютный путь
  *
- * @see DirectAssetReference
+ * @see AssetPath
  */
-class DirectAssetReferenceFactory(val remapper: PathStack) : TypeAdapterFactory {
+class AssetPathFactory(val remapper: PathStack) : TypeAdapterFactory {
 	override fun <T : Any?> create(gson: Gson, type: TypeToken<T>): TypeAdapter<T>? {
-		if (type.rawType == DirectAssetReference::class.java) {
-			return object : TypeAdapter<DirectAssetReference>() {
+		if (type.rawType == AssetPath::class.java) {
+			return object : TypeAdapter<AssetPath>() {
 				private val strings = gson.getAdapter(String::class.java)
 
-				override fun write(out: JsonWriter, value: DirectAssetReference?) {
+				override fun write(out: JsonWriter, value: AssetPath?) {
 					if (value == null)
 						out.nullValue()
 					else
 						out.value(value.fullPath)
 				}
 
-				override fun read(`in`: JsonReader): DirectAssetReference? {
+				override fun read(`in`: JsonReader): AssetPath? {
 					val path = strings.read(`in`) ?: return null
 					if (path == "") return null
-					return DirectAssetReference(path, remapper.remap(path))
+					return AssetPath(path, remapper.remap(path))
 				}
 			} as TypeAdapter<T>
 		}
@@ -41,4 +41,4 @@ class DirectAssetReferenceFactory(val remapper: PathStack) : TypeAdapterFactory
 /**
  * Путь как указан в JSON + Абсолютный путь
  */
-data class DirectAssetReference(val path: String, val fullPath: String)
+data class AssetPath(val path: String, val fullPath: String)
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/IScriptable.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/IScriptable.kt
index 362782c0..d01117f7 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/IScriptable.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/IScriptable.kt
@@ -9,7 +9,7 @@ interface IScriptable {
 	/**
 	 * Lua скрипты для выполнения
 	 */
-	val scripts: List<DirectAssetReference>
+	val scripts: List<AssetPath>
 
 	/**
 	 * Через какое количество тиков вызывать обновления скриптов
@@ -18,7 +18,7 @@ interface IScriptable {
 
 	@JsonFactory
 	data class Impl(
-		override val scripts: ImmutableList<DirectAssetReference> = ImmutableList.of(),
+		override val scripts: ImmutableList<AssetPath> = ImmutableList.of(),
 		override val scriptDelta: Int = 1
 	) : IScriptable
 }
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/StatusEffectDefinition.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/StatusEffectDefinition.kt
index 6d35cead..66624c43 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/StatusEffectDefinition.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/StatusEffectDefinition.kt
@@ -12,7 +12,7 @@ data class StatusEffectDefinition(
 	val blockingStat: String? = null,
 	val label: String? = null,
 	val icon: ImageReference? = null,
-	override val scripts: ImmutableList<DirectAssetReference> = ImmutableList.of(),
+	override val scripts: ImmutableList<AssetPath> = ImmutableList.of(),
 	override val scriptDelta: Int = 1,
 	val animationConfig: AssetReference<AnimationDefinition>? = null,
 ) : IScriptable
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/image/ImageReference.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/image/ImageReference.kt
index 110ea88a..2ec813f8 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/image/ImageReference.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/image/ImageReference.kt
@@ -8,7 +8,7 @@ import com.google.gson.reflect.TypeToken
 import com.google.gson.stream.JsonReader
 import com.google.gson.stream.JsonToken
 import com.google.gson.stream.JsonWriter
-import ru.dbotthepony.kstarbound.defs.DirectAssetReference
+import ru.dbotthepony.kstarbound.defs.AssetPath
 import ru.dbotthepony.kstarbound.util.PathStack
 import ru.dbotthepony.kstarbound.util.SBPattern
 
@@ -16,7 +16,7 @@ import ru.dbotthepony.kstarbound.util.SBPattern
  * @see [AtlasConfiguration.Registry.get]
  */
 class ImageReference private constructor(
-	val raw: DirectAssetReference,
+	val raw: AssetPath,
 	val imagePath: SBPattern,
 	val spritePath: SBPattern?,
 	val atlas: AtlasConfiguration?,
@@ -111,9 +111,9 @@ class ImageReference private constructor(
 
 						if (imagePath.isPlainString) {
 							val remapped = remapper.remap(split[0])
-							return ImageReference(DirectAssetReference(path, remapper.remap(path)), SBPattern.raw(remapped), spritePath, atlasLocator.invoke(remapped), atlasLocator)
+							return ImageReference(AssetPath(path, remapper.remap(path)), SBPattern.raw(remapped), spritePath, atlasLocator.invoke(remapped), atlasLocator)
 						} else {
-							return ImageReference(DirectAssetReference(path, path), imagePath, spritePath, null, atlasLocator)
+							return ImageReference(AssetPath(path, path), imagePath, spritePath, null, atlasLocator)
 						}
 					}
 				} as TypeAdapter<T>
@@ -124,6 +124,6 @@ class ImageReference private constructor(
 	}
 
 	companion object {
-		val NEVER = ImageReference(DirectAssetReference("", ""), SBPattern.EMPTY, null, null) { null }
+		val NEVER = ImageReference(AssetPath("", ""), SBPattern.EMPTY, null, null) { null }
 	}
 }
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/item/TreasurePoolDefinition.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/item/TreasurePoolDefinition.kt
index a2125356..2dfbd7e0 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/item/TreasurePoolDefinition.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/item/TreasurePoolDefinition.kt
@@ -65,10 +65,10 @@ class TreasurePoolDefinition(pieces: List<Piece>) {
 
 			for (round in 0 until rounds) {
 				for (entry in fill) {
-					entry.run(left = {
+					entry.map({
 						val stack = it.makeStack()
 						if (stack.isNotEmpty) result.add(stack)
-					}, right = {
+					}, {
 						it.value?.value?.evaluate(random, actualLevel)
 					})
 				}
@@ -78,10 +78,10 @@ class TreasurePoolDefinition(pieces: List<Piece>) {
 
 					for (entry in pool) {
 						if (chosen <= entry.weight) {
-							entry.treasure.run(left = {
+							entry.treasure.map({
 								val stack = it.makeStack()
 								if (stack.isNotEmpty) result.add(stack)
-							}, right = {
+							}, {
 								it.value?.value?.evaluate(random, actualLevel)
 							})
 
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/item/impl/ArmorItemDefinition.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/item/impl/ArmorItemDefinition.kt
index d8aa7a79..40a06b07 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/item/impl/ArmorItemDefinition.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/item/impl/ArmorItemDefinition.kt
@@ -1,12 +1,10 @@
 package ru.dbotthepony.kstarbound.defs.item.impl
 
 import com.google.common.collect.ImmutableList
-import ru.dbotthepony.kstarbound.defs.DirectAssetReference
 import ru.dbotthepony.kstarbound.defs.IScriptable
 import ru.dbotthepony.kstarbound.defs.item.api.IArmorItemDefinition
 import ru.dbotthepony.kstarbound.defs.item.LeveledStatusEffect
 import ru.dbotthepony.kstarbound.defs.item.api.IItemDefinition
-import ru.dbotthepony.kstarbound.io.json.builder.JsonBuilder
 import ru.dbotthepony.kstarbound.io.json.builder.JsonFactory
 import ru.dbotthepony.kstarbound.io.json.builder.JsonFlat
 
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/monster/MonsterTypeDefinition.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/monster/MonsterTypeDefinition.kt
index 0e705852..dda58afa 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/monster/MonsterTypeDefinition.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/monster/MonsterTypeDefinition.kt
@@ -4,7 +4,6 @@ import com.google.common.collect.ImmutableList
 import com.google.common.collect.ImmutableMap
 import com.google.common.collect.ImmutableSet
 import ru.dbotthepony.kstarbound.defs.AssetReference
-import ru.dbotthepony.kstarbound.defs.DirectAssetReference
 import ru.dbotthepony.kstarbound.defs.IScriptable
 import ru.dbotthepony.kstarbound.defs.IThingWithDescription
 import ru.dbotthepony.kstarbound.defs.MovementParameters
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/CompanionsConfig.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/CompanionsConfig.kt
index a1b75cba..323ca27c 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/CompanionsConfig.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/CompanionsConfig.kt
@@ -2,14 +2,14 @@ package ru.dbotthepony.kstarbound.defs.player
 
 import com.google.common.collect.ImmutableList
 import com.google.common.collect.ImmutableMap
-import ru.dbotthepony.kstarbound.defs.DirectAssetReference
+import ru.dbotthepony.kstarbound.defs.AssetPath
 import ru.dbotthepony.kstarbound.defs.IScriptable
 import ru.dbotthepony.kstarbound.util.SBPattern
 import ru.dbotthepony.kstarbound.io.json.builder.JsonFactory
 
 @JsonFactory
 data class CompanionsConfig(
-	override val scripts: ImmutableList<DirectAssetReference>,
+	override val scripts: ImmutableList<AssetPath>,
 	override val scriptDelta: Int,
 
 	val activePodLimit: Int,
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/DeploymentConfig.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/DeploymentConfig.kt
index 0543b1e0..d6fdd86d 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/DeploymentConfig.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/DeploymentConfig.kt
@@ -2,7 +2,7 @@ package ru.dbotthepony.kstarbound.defs.player
 
 import com.google.common.collect.ImmutableList
 import com.google.common.collect.ImmutableMap
-import ru.dbotthepony.kstarbound.defs.DirectAssetReference
+import ru.dbotthepony.kstarbound.defs.AssetPath
 import ru.dbotthepony.kstarbound.defs.IScriptable
 import ru.dbotthepony.kstarbound.defs.RegistryReference
 import ru.dbotthepony.kstarbound.defs.item.api.IItemDefinition
@@ -10,7 +10,7 @@ import ru.dbotthepony.kstarbound.io.json.builder.JsonFactory
 
 @JsonFactory
 data class DeploymentConfig(
-	override val scripts: ImmutableList<DirectAssetReference>,
+	override val scripts: ImmutableList<AssetPath>,
 	override val scriptDelta: Int,
 
 	val starterMechSet: ImmutableMap<String, RegistryReference<IItemDefinition>>,
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/TechDefinition.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/TechDefinition.kt
index bd5fe913..3a3e6d46 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/TechDefinition.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/player/TechDefinition.kt
@@ -1,7 +1,7 @@
 package ru.dbotthepony.kstarbound.defs.player
 
 import com.google.common.collect.ImmutableList
-import ru.dbotthepony.kstarbound.defs.DirectAssetReference
+import ru.dbotthepony.kstarbound.defs.AssetPath
 import ru.dbotthepony.kstarbound.defs.IScriptable
 import ru.dbotthepony.kstarbound.io.json.builder.JsonFactory
 
@@ -11,5 +11,5 @@ data class TechDefinition(
 	val type: String,
 	val chipCost: Int,
 	override val scriptDelta: Int = 1,
-	override val scripts: ImmutableList<DirectAssetReference>
+	override val scripts: ImmutableList<AssetPath>
 ) : IScriptable
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/quest/QuestTemplate.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/quest/QuestTemplate.kt
index 9c4bb113..6efaa8ee 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/defs/quest/QuestTemplate.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/defs/quest/QuestTemplate.kt
@@ -2,7 +2,7 @@ package ru.dbotthepony.kstarbound.defs.quest
 
 import com.google.common.collect.ImmutableSet
 import com.google.gson.JsonObject
-import ru.dbotthepony.kstarbound.defs.DirectAssetReference
+import ru.dbotthepony.kstarbound.defs.AssetPath
 import ru.dbotthepony.kstarbound.io.json.builder.JsonFactory
 
 @JsonFactory
@@ -10,7 +10,7 @@ data class QuestTemplate(
 	val id: String,
 	val prerequisites: ImmutableSet<String> = ImmutableSet.of(),
 	val requiredItems: ImmutableSet<String> = ImmutableSet.of(),
-	val script: DirectAssetReference,
+	val script: AssetPath,
 	val updateDelta: Int = 10,
 	val moneyRange: LongRange,
 	val scriptConfig: JsonObject = JsonObject()
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/io/json/EitherTypeAdapter.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/io/json/EitherTypeAdapter.kt
index 79f83c19..b1446d32 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/io/json/EitherTypeAdapter.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/io/json/EitherTypeAdapter.kt
@@ -32,7 +32,7 @@ object EitherTypeAdapter : TypeAdapterFactory {
 					if (value == null)
 						out.nullValue()
 					else
-						value.run({ leftAdapter.write(out, it) }, { rightAdapter.write(out, it) })
+						value.map({ leftAdapter.write(out, it) }, { rightAdapter.write(out, it) })
 				}
 
 				override fun read(`in`: JsonReader): Either<Any, Any>? {
diff --git a/src/main/kotlin/ru/dbotthepony/kstarbound/util/Either.kt b/src/main/kotlin/ru/dbotthepony/kstarbound/util/Either.kt
index 0cf8051f..5af51a08 100644
--- a/src/main/kotlin/ru/dbotthepony/kstarbound/util/Either.kt
+++ b/src/main/kotlin/ru/dbotthepony/kstarbound/util/Either.kt
@@ -7,35 +7,81 @@ import ru.dbotthepony.kstarbound.io.json.EitherTypeAdapter
  *
  * JSON адаптер реализуется через [EitherTypeAdapter]
  */
-data class Either<L : Any, R : Any>(val left: L?, val right: R?) {
-	init {
-		require(left != null || right != null) { "Both inputs are null" }
-		require(!(left != null && right != null)) { "Both inputs are not null" }
+sealed class Either<L, R> {
+	class Left<L, R>(val value: L) : Either<L, R>() {
+		override val isLeft: Boolean
+			get() = true
+		override val isRight: Boolean
+			get() = false
+
+		override fun <T> map(left: (L) -> T, right: (R) -> T): T {
+			return left.invoke(this.value)
+		}
+
+		override fun left(): L {
+			return value
+		}
+
+		override fun right(): R {
+			throw NoSuchElementException()
+		}
 	}
 
-	inline fun run(left: (L) -> Unit, right: (R) -> Unit) {
-		if (this.left != null)
-			left.invoke(this.left)
-		else
-			right.invoke(this.right!!)
+	class Right<L, R>(val value: R) : Either<L, R>() {
+		override val isLeft: Boolean
+			get() = false
+		override val isRight: Boolean
+			get() = true
+
+		override fun <T> map(left: (L) -> T, right: (R) -> T): T {
+			return right.invoke(value)
+		}
+
+		override fun left(): L {
+			throw NoSuchElementException()
+		}
+
+		override fun right(): R {
+			return value
+		}
 	}
 
-	inline fun <T> reduce(left: (L) -> T, right: (R) -> T): T {
-		return if (this.left != null)
-			left.invoke(this.left)
+	abstract val isLeft: Boolean
+	abstract val isRight: Boolean
+
+	abstract fun <T> map(left: (L) -> T, right: (R) -> T): T
+
+	/**
+	 * @throws NoSuchElementException
+	 */
+	abstract fun left(): L
+
+	/**
+	 * @throws NoSuchElementException
+	 */
+	abstract fun right(): R
+
+	inline fun leftOrElse(orElse: () -> L): L {
+		if (isLeft)
+			return left()
 		else
-			right.invoke(this.right!!)
+			return orElse.invoke()
+	}
+
+	inline fun rightOrElse(orElse: () -> R): R {
+		if (isRight)
+			return right()
+		else
+			return orElse.invoke()
 	}
 
 	companion object {
-		@JvmStatic
-		fun <L : Any, R : Any> left(value: L): Either<L, R> {
-			return Either(left = value, right = null)
+		fun <L, R> left(value: L): Either<L, R> {
+			return Left(value)
 		}
 
-		@JvmStatic
-		fun <L : Any, R : Any> right(value: R): Either<L, R> {
-			return Either(left = null, right = value)
+		fun <L, R> right(value: R): Either<L, R> {
+			return Right(value)
 		}
 	}
 }