diff --git a/assets/worldIcons/down-arrow.png b/assets/worldIcons/down-arrow.png
new file mode 100644
index 0000000..05e1f5d
Binary files /dev/null and b/assets/worldIcons/down-arrow.png differ
diff --git a/assets/worldIcons/up-arrow.png b/assets/worldIcons/up-arrow.png
new file mode 100644
index 0000000..d7aa133
Binary files /dev/null and b/assets/worldIcons/up-arrow.png differ
diff --git a/src/game/GameLayer.cpp b/src/game/GameLayer.cpp
index 71667be..17522d7 100644
--- a/src/game/GameLayer.cpp
+++ b/src/game/GameLayer.cpp
@@ -66,6 +66,7 @@ void GameLayer::onAttach()
 
     auto modelTexture = AssetManager::loadTexture("warning", "assets/worldIcons/warning.png", loader);
     AssetManager::loadTexture("error", "assets/worldIcons/error.png", loader);
+    AssetManager::loadTexture("upgrade", "assets/worldIcons/up-arrow.png", loader);
 
 
     events.subscribe<TurnChangedEvent>([this](const TurnChangedEvent& event) {
@@ -108,7 +109,15 @@ void GameLayer::onUpdate()
 
     if (gameInputUser->isKeyboardEnabled()) {
         if (Application::getInstance().keyboard->keyPressEvent(GLFW_KEY_U)) {
-            gameMode->setUpgradeMode(!gameMode->isUpgradeMode());
+            if (gameMode->isUpgradeMode()) {
+                // Disable upgrade mode in upgrade system
+                UpgradeSystem::disableUpgradeMode(*entityManager, gameMode->getCurrentPlayer(), *gameMode);
+                gameMode->setUpgradeMode(false);
+            } else {
+                UpgradeSystem::enableUpgradeMode(*entityManager, gameMode->getCurrentPlayer(), *gameMode, *turnState);
+                gameMode->setUpgradeMode(true);
+            }
+
         }
     }
 
diff --git a/src/game/hexWorld/ecs/systems/UpgradeSystem.cpp b/src/game/hexWorld/ecs/systems/UpgradeSystem.cpp
index 86c2ac7..eede14b 100644
--- a/src/game/hexWorld/ecs/systems/UpgradeSystem.cpp
+++ b/src/game/hexWorld/ecs/systems/UpgradeSystem.cpp
@@ -15,7 +15,13 @@
 #include "../../../../engine/core/ECS/TileRenderComponent.h"
 #include "../../../../engine/core/ECS/ModelComponent.h"
 #include "../../../../engine/core/ECS/ModelStateComponent.h"
+#include "../../../../engine/renderer/loader/AssetManager.h"
 #include "../components/TileGameplayComponent.h"
+#include "../../../../engine/core/ECS/WorldSpriteComponent.h"
+#include "../../../../engine/core/animations/AnimationComponent.h"
+
+class AnimationComponent;
+class WorldSpriteComponent;
 
 void UpgradeSystem::tryUpdate(EntityManager &em, GameMode &gm, PlayerID player, const TurnState &turnState) {
     EntityID tileEntityID = SelectionSystem::selectedEntity;
@@ -55,6 +61,34 @@ void UpgradeSystem::tryUpdate(EntityManager &em, GameMode &gm, PlayerID player,
 
 }
 
+void UpgradeSystem::enableUpgradeMode(EntityManager &em, PlayerID player, GameMode& gameMode, const TurnState &turnState) {
+    for (EntityID entityID : em.getAllEntities()) {
+        auto buildingComponent = em.getComponent<BuildingComponent>(entityID);
+        auto ownerComponent = em.getComponent<OwnerComponent>(entityID);
+
+        if (buildingComponent && ownerComponent && ownerComponent->playerID == player) {
+            const auto upgradeResult = canUpgrade(em, player, gameMode, entityID, turnState);
+            if (upgradeResult == UpgradeResult::Ok || upgradeResult == UpgradeResult::NotPlayersTurn) {
+                createWorldSprite(em, entityID);
+            }
+        }
+    }
+}
+
+void UpgradeSystem::disableUpgradeMode(EntityManager &em, PlayerID player, GameMode &gameMode) {
+    for (EntityID entityID : em.getAllEntities()) {
+        const auto buildingComponent = em.getComponent<BuildingComponent>(entityID);
+        const auto ownerComponent = em.getComponent<OwnerComponent>(entityID);
+        const auto worldSpriteComponent = em.getComponent<WorldSpriteComponent>(entityID);
+        const auto animComponent = em.getComponent<AnimationComponent>(entityID);
+
+        if (buildingComponent && ownerComponent && ownerComponent->playerID == player && worldSpriteComponent) {
+            em.removeComponent<WorldSpriteComponent>(entityID);
+            em.removeComponent<AnimationComponent>(entityID);
+        }
+    }
+}
+
 UpgradeResult UpgradeSystem::canUpgrade(EntityManager &em, PlayerID player, GameMode& gameMode, EntityID buildingEntity, const TurnState &turnState) {
     if (!gameMode.hasTurn(player, turnState.currentTurn)) return UpgradeResult::NotPlayersTurn;
 
@@ -78,3 +112,34 @@ UpgradeResult UpgradeSystem::canUpgrade(EntityManager &em, PlayerID player, Game
 
     return UpgradeResult::Ok;
 }
+
+void UpgradeSystem::createWorldSprite(EntityManager &em, EntityID e) {
+    auto iconTexture = AssetManager::getTexture("upgrade");
+
+    auto worldSpritePtr = std::make_shared<WorldSpriteComponent>();
+    std::weak_ptr<WorldSpriteComponent> weakSprite = worldSpritePtr;
+    worldSpritePtr->texture = iconTexture;
+    worldSpritePtr->iconName = "upgrade";
+
+    auto anim = std::make_shared<AnimationComponent>();
+
+    float baseY = worldSpritePtr->offset.y;
+
+    anim->tracks.push_back({
+        AnimationCurve{CurveType::Sine, 0.3f, 5.f},
+        [weakSprite, baseY](float v) {
+            if (auto sprite = weakSprite.lock()) {
+                sprite->offset.y = baseY + v;
+            }
+        }
+    });
+
+    if (!em.getComponent<WorldSpriteComponent>(e)) {
+        em.addComponent(e, worldSpritePtr);
+    }
+
+    if (!em.getComponent<AnimationComponent>(e)) {
+        em.addComponent(e, anim);
+    }
+}
+
diff --git a/src/game/hexWorld/ecs/systems/UpgradeSystem.h b/src/game/hexWorld/ecs/systems/UpgradeSystem.h
index d122edb..790b77e 100644
--- a/src/game/hexWorld/ecs/systems/UpgradeSystem.h
+++ b/src/game/hexWorld/ecs/systems/UpgradeSystem.h
@@ -21,7 +21,11 @@ class EntityManager;
 class UpgradeSystem {
 public:
     static void tryUpdate(EntityManager &em, GameMode &gm, PlayerID player, const TurnState &turnState);
+    static void enableUpgradeMode(EntityManager &em, PlayerID player, GameMode& gameMode, const TurnState &turnState);
+    static void disableUpgradeMode(EntityManager &em, PlayerID player, GameMode& gameMode);
 
+private:
+    static void createWorldSprite(EntityManager &em, EntityID e);
     static UpgradeResult canUpgrade(EntityManager &em, PlayerID player, GameMode &gameMode, EntityID buildingEntity, const TurnState &turnState);
 };