diff --git a/src/main/kotlin/ru/dbotthepony/mc/otm/android/AndroidResearchType.kt b/src/main/kotlin/ru/dbotthepony/mc/otm/android/AndroidResearchType.kt
index 8c75057fb..8ef214791 100644
--- a/src/main/kotlin/ru/dbotthepony/mc/otm/android/AndroidResearchType.kt
+++ b/src/main/kotlin/ru/dbotthepony/mc/otm/android/AndroidResearchType.kt
@@ -256,6 +256,13 @@ open class AndroidResearchType<R : AndroidResearch>(
 			set.addAll(research.allUnlocks)
 		}
 
+		for (research in allPrerequisites) {
+			for (research2 in research.flatBlocking) {
+				set.add(research2)
+				set.addAll(research2.allUnlocks)
+			}
+		}
+
 		ListSet(set)
 	}
 
diff --git a/src/main/kotlin/ru/dbotthepony/mc/otm/client/render/Ext.kt b/src/main/kotlin/ru/dbotthepony/mc/otm/client/render/Ext.kt
index 2c7786f19..129b21805 100644
--- a/src/main/kotlin/ru/dbotthepony/mc/otm/client/render/Ext.kt
+++ b/src/main/kotlin/ru/dbotthepony/mc/otm/client/render/Ext.kt
@@ -1,6 +1,7 @@
 package ru.dbotthepony.mc.otm.client.render
 
 import com.mojang.blaze3d.vertex.PoseStack
+import com.mojang.blaze3d.vertex.Tesselator
 import com.mojang.blaze3d.vertex.VertexConsumer
 import com.mojang.math.Matrix4f
 import com.mojang.math.Vector3f
@@ -10,6 +11,8 @@ import net.minecraft.network.chat.Component
 import net.minecraft.util.FormattedCharSequence
 import ru.dbotthepony.mc.otm.core.*
 
+val tesselator: Tesselator get() = Tesselator.getInstance()
+
 fun VertexConsumer.normal(vector: Vector): VertexConsumer = normal(vector.x.toFloat(), vector.y.toFloat(), vector.z.toFloat())
 fun VertexConsumer.vertex(matrix4f: Matrix4f, vector: Vector): VertexConsumer = vertex(matrix4f, vector.x.toFloat(), vector.y.toFloat(), vector.z.toFloat())
 fun VertexConsumer.color(color: RGBAColor): VertexConsumer = color(color.red, color.green, color.blue, color.alpha)
diff --git a/src/main/kotlin/ru/dbotthepony/mc/otm/client/render/RenderHelper.kt b/src/main/kotlin/ru/dbotthepony/mc/otm/client/render/RenderHelper.kt
index 768b87467..24052188b 100644
--- a/src/main/kotlin/ru/dbotthepony/mc/otm/client/render/RenderHelper.kt
+++ b/src/main/kotlin/ru/dbotthepony/mc/otm/client/render/RenderHelper.kt
@@ -40,7 +40,7 @@ fun drawTexturedRect(
 	RenderSystem.defaultBlendFunc()
 	RenderSystem.depthFunc(GL11.GL_ALWAYS)
 
-	val builder = Tesselator.getInstance().builder
+	val builder = tesselator.builder
 
 	builder.begin(VertexFormat.Mode.QUADS, DefaultVertexFormat.POSITION_TEX)
 	builder.vertex(matrix, x, y + height, zLevel).uv(u0, v1).endVertex()
@@ -105,7 +105,7 @@ fun colorSphere(matrix: Matrix4f, radius: Float) {
 	RenderSystem.enableBlend()
 	RenderSystem.defaultBlendFunc()
 
-	val builder = Tesselator.getInstance().builder
+	val builder = tesselator.builder
 	builder.begin(VertexFormat.Mode.QUADS, DefaultVertexFormat.POSITION_COLOR)
 
 	val turnStep = Math.PI * (1 / fragments.toDouble()) * 2
@@ -299,7 +299,7 @@ fun drawRect(
 	RenderSystem.setShader(GameRenderer::getPositionColorShader)
 	RenderSystem.depthFunc(GL11.GL_ALWAYS)
 
-	val tess = Tesselator.getInstance()
+	val tess = tesselator
 	val builder = tess.builder
 
 	builder.begin(VertexFormat.Mode.QUADS, DefaultVertexFormat.POSITION_COLOR)
diff --git a/src/main/kotlin/ru/dbotthepony/mc/otm/client/screen/AndroidStationScreen.kt b/src/main/kotlin/ru/dbotthepony/mc/otm/client/screen/AndroidStationScreen.kt
index 74bde26ee..22f3a28a0 100644
--- a/src/main/kotlin/ru/dbotthepony/mc/otm/client/screen/AndroidStationScreen.kt
+++ b/src/main/kotlin/ru/dbotthepony/mc/otm/client/screen/AndroidStationScreen.kt
@@ -20,6 +20,7 @@ import ru.dbotthepony.mc.otm.android.AndroidResearchType
 import ru.dbotthepony.mc.otm.capability.AndroidCapability
 import ru.dbotthepony.mc.otm.capability.MatteryCapability
 import ru.dbotthepony.mc.otm.client.minecraft
+import ru.dbotthepony.mc.otm.client.render.Widgets18
 import ru.dbotthepony.mc.otm.client.render.drawColor
 import ru.dbotthepony.mc.otm.client.render.drawLine
 import ru.dbotthepony.mc.otm.client.render.drawRect
@@ -281,28 +282,42 @@ private open class AndroidResearchButton(
 	}
 
 	override fun innerRender(stack: PoseStack, mouse_x: Float, mouse_y: Float, flag: Float) {
-		minecraft.player?.getCapability(MatteryCapability.ANDROID)?.ifPresentK {
-			if (node.isResearched) {
-				AndroidStationScreen.RESEARCHED.setSystemColor()
-			} else if (node.canResearch) {
-				AndroidStationScreen.CAN_BE_RESEARCHED.setSystemColor()
-			} else {
-				AndroidStationScreen.CAN_NOT_BE_RESEARCHED.setSystemColor()
-			}
+		val hovered = (screen as AndroidStationScreen).hoveredResearch
 
-			val icon = node.skinIcon
+		val isBlockedByHovered = hovered != null && node.type in hovered.type.allBlocking
 
-			if (icon != null) {
-				icon.render(stack, 0f, 0f, width, height)
-			} else {
-				drawRect(stack, 0f, 0f, width, height)
-			}
+		if (isBlockedByHovered) {
+			AndroidStationScreen.CAN_NOT_BE_RESEARCHED.setSystemColor()
 
-			val text = node.iconText
+			drawRect(stack, 0f, 0f, width, height)
+		}
 
-			if (text != null) {
-				font.drawShadow(stack, text, width - font.width(text), height - font.lineHeight, -0x1)
-			}
+		if (node.isResearched) {
+			AndroidStationScreen.RESEARCHED.setSystemColor()
+		} else if (node.canResearch) {
+			AndroidStationScreen.CAN_BE_RESEARCHED.setSystemColor()
+		} else {
+			AndroidStationScreen.CAN_NOT_BE_RESEARCHED.setSystemColor()
+		}
+
+		val icon = node.skinIcon
+
+		if (icon != null) {
+			icon.render(stack, 0f, 0f, width, height)
+		} else {
+			drawRect(stack, 0f, 0f, width, height)
+		}
+
+		if (isBlockedByHovered) {
+			RGBAColor.RED.setSystemColor()
+
+			Widgets18.CROSS.render(stack)
+		}
+
+		val text = node.iconText
+
+		if (text != null) {
+			font.drawShadow(stack, text, width - font.width(text), height - font.lineHeight, -0x1)
 		}
 
 		drawColor = RGBAColor.WHITE
@@ -316,7 +331,7 @@ private open class AndroidResearchButton(
 			drawLine(stack, x1, y1, x2, y2, 0.5f)
 		}
 
-		val hovered = (screen as AndroidStationScreen).hoveredResearch ?: return
+		hovered ?: return
 		val lines = highlightLines[hovered.type] ?: return
 
 		drawColor = RGBAColor.LIGHT_GREEN
diff --git a/src/main/kotlin/ru/dbotthepony/mc/otm/core/RGBAColor.kt b/src/main/kotlin/ru/dbotthepony/mc/otm/core/RGBAColor.kt
index c4b1b7458..c84eaf7e7 100644
--- a/src/main/kotlin/ru/dbotthepony/mc/otm/core/RGBAColor.kt
+++ b/src/main/kotlin/ru/dbotthepony/mc/otm/core/RGBAColor.kt
@@ -53,6 +53,7 @@ data class RGBAColor(val red: Float, val green: Float, val blue: Float, val alph
 	companion object {
 		val BLACK = RGBAColor(0f, 0f, 0f, 1f)
 		val WHITE = RGBAColor(1f, 1f, 1f, 1f)
+		val RED = RGBAColor(1f, 0f, 0f)
 		val GREEN = RGBAColor(0f, 1f, 0f, 1f)
 		val LIGHT_GREEN = RGBAColor(136, 255, 124)
 		val SLATE_GRAY = RGBAColor(64, 64, 64)
diff --git a/src/main/resources/assets/overdrive_that_matters/textures/gui/widgets_18.png b/src/main/resources/assets/overdrive_that_matters/textures/gui/widgets_18.png
index faa5401c5..3ae0818c4 100644
Binary files a/src/main/resources/assets/overdrive_that_matters/textures/gui/widgets_18.png and b/src/main/resources/assets/overdrive_that_matters/textures/gui/widgets_18.png differ