diff --git a/README.md b/README.md
index 43eb5f3..cbc732f 100644
--- a/README.md
+++ b/README.md
@@ -15,11 +15,11 @@ This game is aimed to be a puzzle game in which the player sets different laws f
   - [x] Structure
   - [x] Parsing from XML
   - [x] A*
- - [ ] Entities
+ - [x] Entities
   - [x] Structure
   - [x] Parsing from XML
   - [x] Moving
-  - [ ] Decorators (Rules)
+  - [x] Decorators (Rules)
  - [ ] Rules
   - [x] Creation
   - [x] Interaction with entities
@@ -32,7 +32,7 @@ This game is aimed to be a puzzle game in which the player sets different laws f
  - [ ] Gameloop
   - [ ] Transition from starting to running state and vice-versa
   - [ ] Entity behaviour evolution
-  - [ ] Rule application
+  - [x] Rule application
   - [ ] Saving state through serialization ?
  - [ ] UML
  - [ ] Unit tests
\ No newline at end of file
diff --git a/src/Entity.cpp b/src/Entity.cpp
index 987eaa3..11cc6c6 100644
--- a/src/Entity.cpp
+++ b/src/Entity.cpp
@@ -79,6 +79,11 @@ State Entity::getState() const
     return currentState;
 }
 
+EntityType Entity::getType() const
+{
+    return type;
+}
+
 pro_maat::GridPos Entity::getTarget() const
 {
     return target;
diff --git a/src/Entity.h b/src/Entity.h
index 081f956..3765a09 100644
--- a/src/Entity.h
+++ b/src/Entity.h
@@ -51,6 +51,7 @@ public:
     virtual void update();
 
     virtual State getState() const;
+    virtual EntityType getType() const;
     virtual pro_maat::GridPos getTarget() const;
 
     virtual const sf::RectangleShape& getShape() const;
@@ -84,7 +85,6 @@ private:
     /// Used with rules : last to update has priority
     pro_maat::GridPos nextTarget;
 
-    template<State targetState, EntityType targetType>
     friend class Rule;
 };
 
diff --git a/src/Level.cpp b/src/Level.cpp
index 2e4a2cb..65633b4 100644
--- a/src/Level.cpp
+++ b/src/Level.cpp
@@ -14,24 +14,34 @@ Level::Level(const pugi::xml_document& xmlDoc, const pro_maat::TextureStore& tex
     {
         if(!strncmp(child.name(),"Entity",6))
         {
-            entities.emplace_back(child,textures.at(child.attribute("textureId").as_int(0)).get());
+            entities.emplace_back(std::make_unique<Entity>(child,textures.at(child.attribute("textureId").as_int(0)).get()));
 
             // Initialize the occupied squares vector with the new entity's squares
-            std::vector<pro_maat::GridPos> entitySquares = entities.rbegin()->getOccupiedSquares();
-
-            // FIXME : For testing purposes
-            Rule<State::Moving,EntityType::House> newRule(*entities.rbegin(),entities,occupiedSquares,size);
-
+            std::vector<pro_maat::GridPos> entitySquares = entities.rbegin()->get()->getOccupiedSquares();
             std::move(entitySquares.begin(),entitySquares.end(),std::back_inserter(occupiedSquares));
         }
     }
+
+    // FIXME : For testing purposes
+    addRule(EntityType::Significant,State::Moving,EntityType::Citizen);
+}
+
+void Level::addRule(EntityType affectedEntities, const State targetState, EntityType targetEntities)
+{
+    for(auto& entity : entities)
+    {
+        if(entity->getType() == affectedEntities)
+        {
+            entity = std::make_unique<Rule>(entity.release(),targetState,targetEntities,entities,occupiedSquares,size);
+        }
+    }
 }
 
 void Level::render(sf::RenderWindow& renderWindow) const
 {
-    for(const Entity& entity : entities)
+    for(const auto& entity : entities)
     {
-        renderWindow.draw(entity.getShape());
+        renderWindow.draw(entity->getShape());
     }
 }
 
@@ -40,11 +50,11 @@ void Level::runStep()
     std::vector<pro_maat::GridPos> newOccupiedSquares{};
     newOccupiedSquares.reserve(occupiedSquares.size());
 
-    for(Entity& entity: entities)
+    for(auto& entity: entities)
     {
-        entity.update();
+        entity->update();
         int heuristicSign = 0;
-        switch (entity.getState())
+        switch (entity->getState())
         {
             case State::Moving:
             {
@@ -57,9 +67,9 @@ void Level::runStep()
                 {
                     heuristicSign = -1;
                 }
-                if(entity.getTarget() != entity.getPosition())
+                if(entity->getTarget() != entity->getPosition())
                 {
-                    entity.move(findPath(entity.getPosition(),entity.getTarget(),heuristicSign));
+                    entity->move(findPath(entity->getPosition(),entity->getTarget(),heuristicSign));
                 }
                 break;
             }
@@ -67,7 +77,7 @@ void Level::runStep()
             case State::Idle:break;
         }
 
-        std::vector<pro_maat::GridPos> entitySquares = entity.getOccupiedSquares();
+        std::vector<pro_maat::GridPos> entitySquares = entity->getOccupiedSquares();
 
         // FIXME : Very heavy memory usage and a lot of duplicates, slows down occupiedSquares.find() calls too.
         // Copy the squares to the currently occupied squares : prevents moving into an entity that just moved
diff --git a/src/Level.h b/src/Level.h
index f6219c6..0171da9 100644
--- a/src/Level.h
+++ b/src/Level.h
@@ -21,13 +21,20 @@ class Level {
 public:
     Level(const pugi::xml_document& xmlDoc, const pro_maat::TextureStore& textureStore);
 
+    /// Add a new rule on top of existing ones, thus with a lower priority
+    ///
+    /// \param affectedEntities Entities to which the rule will be applied
+    /// \param targetState      What action will the rule perform
+    /// \param targetEntities   Which entities will be targeted
+    void addRule(EntityType affectedEntities, State targetState, EntityType targetEntities);
+
     void render(sf::RenderWindow& renderWindow) const;
     void runStep();
 
 private:
     const pro_maat::GridPos size;
 
-    std::vector<Entity> entities;
+    std::vector<std::unique_ptr<Entity>> entities;
 
     const pro_maat::TextureStore& textures;
 
diff --git a/src/Rule.cpp b/src/Rule.cpp
index 3556db6..50b5c1b 100644
--- a/src/Rule.cpp
+++ b/src/Rule.cpp
@@ -3,3 +3,170 @@
 //
 
 #include "Rule.h"
+
+
+Rule::Rule(Entity* entity, State targetState, EntityType targetType,
+           std::vector<std::unique_ptr<Entity>>& entities,
+           const std::vector<pro_maat::GridPos>& occupiedSquares, const pro_maat::GridPos& mapSize)
+        : entity(entity),
+          targetState(targetState),
+          targetType(targetType),
+          entities(entities),
+          occupiedSquares(occupiedSquares),
+          mapSize(mapSize)
+{}
+
+void Rule::update()
+{
+    if (targetState == State::Moving || targetState == State::Fleeing)
+    {
+        entity->nextTarget = findTarget();
+        if(entity->nextTarget == entity->getPosition())
+        {
+            entity->nextState = State::Idle;
+        }
+        else
+        {
+            entity->nextState = targetState;
+        }
+        entity->update();
+    }
+    else if (targetState == State::Waiting)
+    {
+        entity->nextTarget = entity->getPosition();
+        entity->nextState = State::Waiting;
+        entity->update();
+    }
+    else
+    {
+        entity->nextTarget = entity->getPosition();
+        entity->nextState = State::Idle;
+        entity->update();
+    }
+}
+
+pro_maat::GridPos Rule::findTarget()
+{
+    // TODO : Sorting in place, consider using shared_ptr ?
+//    std::vector<Entity> sortedEntities{};
+//    sortedEntities.insert(sortedEntities.end(),entities.begin(),entities.end());
+
+    // Compares entities via their distance to the current entity
+    auto distanceSortEntities = [this](const std::unique_ptr<Entity>& leftHandSide, const std::unique_ptr<Entity>& rightHandSide){
+        return (pro_maat::manhattanDistance(entity->getPosition(),leftHandSide->getPosition()) <
+                pro_maat::manhattanDistance(entity->getPosition(),rightHandSide->getPosition()));
+    };
+
+    // Same but with grid coordinates
+    auto distanceSortSquares = [this](const pro_maat::GridPos& leftHandSide, const pro_maat::GridPos& rightHandSide){
+        return (pro_maat::manhattanDistance(entity->getPosition(),leftHandSide) <
+                pro_maat::manhattanDistance(entity->getPosition(),rightHandSide));
+    };
+
+    // Get the smallest, non-occupied, inside the map square
+    auto bestTarget = [this](const pro_maat::GridPos& leftHandSide, const pro_maat::GridPos& rightHandSide){
+        // If the left hand side operand is not in the map or occupied, it is not valid
+        if(!pro_maat::isInMap(leftHandSide,mapSize) ||
+           std::find(occupiedSquares.begin(),occupiedSquares.end(),leftHandSide) != occupiedSquares.end())
+        {
+            return(false);
+        }
+        else if(!pro_maat::isInMap(rightHandSide,mapSize) ||
+                std::find(occupiedSquares.begin(),occupiedSquares.end(),rightHandSide) != occupiedSquares.end())
+        {
+            return(true);
+        }
+        else
+        {
+            return(leftHandSide < rightHandSide);
+        }};
+
+
+    // Sort in order to minimize entities to process
+    std::sort(entities.begin(),entities.end(),distanceSortEntities);
+
+    for(const auto& processingEntity : entities)
+    {
+        if(processingEntity->getType() != targetType) continue;
+
+        std::vector<pro_maat::GridPos> potentialTargets{};
+
+        pro_maat::GridUnit entityWidth = processingEntity->shape.getSize().x/pro_maat::pixelsPerUnit;
+        pro_maat::GridUnit entityHeight = processingEntity->shape.getSize().y/pro_maat::pixelsPerUnit;
+
+        potentialTargets.reserve((entityWidth+2)*2+entityHeight*2);
+
+        // Computes the top left corner of the entity
+        pro_maat::GridPos topLeftCorner = processingEntity->getPosition();
+        topLeftCorner.first -= entityWidth*0.5 - 1;
+        topLeftCorner.second -= entityHeight*0.5 - 1;
+
+
+        // Get all the top and bottom adjacent squares
+        for(int i = 0;i<entityWidth+2;i++)
+        {
+            potentialTargets.emplace_back(topLeftCorner.first+i,topLeftCorner.second);
+            potentialTargets.emplace_back(topLeftCorner.first+i,topLeftCorner.second+entityHeight+2);
+        }
+        // Get the missing adjacent squares from the sides
+        for(int i = 1;i<=entityHeight;i++)
+        {
+            potentialTargets.emplace_back(topLeftCorner.first,topLeftCorner.second+i);
+            potentialTargets.emplace_back(topLeftCorner.first+entityWidth+2,topLeftCorner.second+i);
+        }
+
+
+        std::sort(potentialTargets.begin(),potentialTargets.end(),distanceSortSquares);
+        auto target = std::min_element(potentialTargets.begin(),potentialTargets.end(),bestTarget);
+
+        if(target != potentialTargets.end())
+        {
+            return (*target);
+        }
+    }
+
+    return (entity->getPosition());
+}
+
+
+////////////////////////
+//                    //
+// Delegate overrides //
+//                    //
+////////////////////////
+
+
+void Rule::move(Orientation orientation)
+{
+    entity->move(orientation);
+}
+
+State Rule::getState() const
+{
+    return entity->getState();
+}
+
+EntityType Rule::getType() const
+{
+    return entity->getType();
+}
+
+const sf::RectangleShape& Rule::getShape() const
+{
+    return entity->getShape();
+}
+
+pro_maat::GridPos Rule::getTarget() const
+{
+    return entity->getTarget();
+}
+
+const pro_maat::GridPos Rule::getPosition() const
+{
+    return entity->getPosition();
+}
+
+const std::vector<pro_maat::GridPos> Rule::getOccupiedSquares() const
+{
+    return entity->getOccupiedSquares();
+}
diff --git a/src/Rule.h b/src/Rule.h
index fae04f9..4215a51 100644
--- a/src/Rule.h
+++ b/src/Rule.h
@@ -12,12 +12,12 @@
 
 
 /// Decorates entities with rules which will modify its behaviour
-template <State targetState, EntityType targetType>
-class Rule : private Entity
+class Rule : public Entity
 {
 public:
-    Rule(Entity& entity, const std::vector<Entity>& entities,
-            const std::vector<pro_maat::GridPos>& occupiedSquares, const pro_maat::GridPos& mapSize);
+    // The Rule object takes ownership of the Entity*
+    Rule(Entity* entity, State targetState, EntityType targetType, std::vector<std::unique_ptr<Entity>>& entities,
+         const std::vector<pro_maat::GridPos>& occupiedSquares, const pro_maat::GridPos& mapSize);
 
     /// Update according to the targetState and targetType
     void update() override;
@@ -26,6 +26,7 @@ public:
 
     void move(Orientation orientation) override;
     State getState() const override;
+    EntityType getType() const override;
     const sf::RectangleShape& getShape() const override;
     pro_maat::GridPos getTarget() const override;
     const pro_maat::GridPos getPosition() const override;
@@ -33,182 +34,20 @@ public:
 
 private:
     /// Finds the closest free square adjacent to the closest target entity type.
+    /// Currently not thread-safe !
     /// \return Suitable target square or current position if none was found.
     pro_maat::GridPos findTarget();
 
-    Entity& entity;
-    const std::vector<Entity>& entities;
+    std::unique_ptr<Entity> entity;
+
+    State targetState;
+    EntityType targetType;
+
+    // TOOD : dropped const-qualifier. Consider using shared_ptr ?
+    std::vector<std::unique_ptr<Entity>>& entities;
     const std::vector<pro_maat::GridPos>& occupiedSquares;
 
     const pro_maat::GridPos& mapSize;
 };
 
-
-template<State targetState, EntityType targetType>
-Rule<targetState, targetType>::Rule(Entity& entity,
-                                    const std::vector<Entity>& entities,
-                                    const std::vector<pro_maat::GridPos>& occupiedSquares,
-                                    const pro_maat::GridPos& mapSize)
-    : entity(entity),
-      entities(entities),
-      occupiedSquares(occupiedSquares),
-      mapSize(mapSize)
-{}
-
-template<State targetState, EntityType targetType>
-void Rule<targetState, targetType>::update()
-{
-    if constexpr (targetState == State::Moving || targetState == State::Fleeing)
-    {
-        entity.nextTarget = findTarget();
-        if(entity.nextTarget == entity.getPosition())
-        {
-            entity.nextState = State::Idle;
-        }
-        else
-        {
-            entity.nextState = targetState;
-        }
-        entity.update();
-    }
-    else if constexpr (targetState == State::Waiting)
-    {
-        entity.nextTarget = entity.getPosition();
-        entity.nextState = State::Waiting;
-        entity.update();
-    }
-    else
-    {
-        entity.nextTarget = entity.getPosition();
-        entity.nextState = State::Idle;
-        entity.update();
-    }
-}
-
-template<State targetState, EntityType targetType>
-pro_maat::GridPos Rule<targetState, targetType>::findTarget()
-{
-    std::vector<Entity> sortedEntities{};
-    sortedEntities.insert(sortedEntities.end(),entities.begin(),entities.end());
-
-    // Compares entities via their distance to the current entity
-    auto distanceSortEntities = [this](const Entity& leftHandSide, const Entity& rightHandSide){
-                                return (pro_maat::manhattanDistance(entity.getPosition(),leftHandSide.getPosition()) <
-                                        pro_maat::manhattanDistance(entity.getPosition(),rightHandSide.getPosition()));
-                                };
-
-    // Same but with grid coordinates
-    auto distanceSortSquares = [this](const pro_maat::GridPos& leftHandSide, const pro_maat::GridPos& rightHandSide){
-                               return (pro_maat::manhattanDistance(entity.getPosition(),leftHandSide) <
-                               pro_maat::manhattanDistance(entity.getPosition(),rightHandSide));
-                               };
-
-    // Get the smallest, non-occupied, inside the map square
-    auto bestTarget = [this](const pro_maat::GridPos& leftHandSide, const pro_maat::GridPos& rightHandSide){
-                       // If the left hand side operand is not in the map or occupied, it is not valid
-                       if(!pro_maat::isInMap(leftHandSide,mapSize) ||
-                          std::find(occupiedSquares.begin(),occupiedSquares.end(),leftHandSide) != occupiedSquares.end())
-                       {
-                           return(false);
-                       }
-                       else if(!pro_maat::isInMap(rightHandSide,mapSize) ||
-                               std::find(occupiedSquares.begin(),occupiedSquares.end(),rightHandSide) != occupiedSquares.end())
-                       {
-                           return(true);
-                       }
-                       else
-                       {
-                           return(leftHandSide < rightHandSide);
-                       }};
-
-
-    // Sort in order to minimize entities to process
-    std::sort(sortedEntities.begin(),sortedEntities.end(),distanceSortEntities);
-
-    for(const Entity& processingEntity : sortedEntities)
-    {
-        std::vector<pro_maat::GridPos> potentialTargets{};
-
-        pro_maat::GridUnit entityWidth = processingEntity.shape.getSize().x/pro_maat::pixelsPerUnit;
-        pro_maat::GridUnit entityHeight = processingEntity.shape.getSize().y/pro_maat::pixelsPerUnit;
-
-        potentialTargets.reserve((entityWidth+2)*2+entityHeight*2);
-
-        // Computes the top left corner of the entity
-        pro_maat::GridPos topLeftCorner = processingEntity.getPosition();
-        topLeftCorner.first -= entityWidth*0.5 - 1;
-        topLeftCorner.second -= entityHeight*0.5 - 1;
-
-
-        // Get all the top and bottom adjacent squares
-        for(int i = 0;i<entityWidth+2;i++)
-        {
-            potentialTargets.emplace_back(topLeftCorner.first+i,topLeftCorner.second);
-            potentialTargets.emplace_back(topLeftCorner.first+i,topLeftCorner.second+entityHeight+2);
-        }
-        // Get the missing adjacent squares from the sides
-        for(int i = 1;i<=entityHeight;i++)
-        {
-            potentialTargets.emplace_back(topLeftCorner.first,topLeftCorner.second+i);
-            potentialTargets.emplace_back(topLeftCorner.first+entityWidth+2,topLeftCorner.second+i);
-        }
-
-
-        std::sort(potentialTargets.begin(),potentialTargets.end(),distanceSortSquares);
-        auto target = std::min_element(potentialTargets.begin(),potentialTargets.end(),bestTarget);
-
-        if(target != potentialTargets.end())
-        {
-            return (*target);
-        }
-    }
-
-    return (entity.getPosition());
-}
-
-
-////////////////////////
-//                    //
-// Delegate overrides //
-//                    //
-////////////////////////
-
-
-template<State targetState, EntityType targetType>
-void Rule<targetState, targetType>::move(Orientation orientation)
-{
-    entity.move(orientation);
-}
-
-template<State targetState, EntityType targetType>
-State Rule<targetState, targetType>::getState() const
-{
-    return entity.getState();
-}
-
-template<State targetState, EntityType targetType>
-const sf::RectangleShape& Rule<targetState, targetType>::getShape() const
-{
-    return entity.getShape();
-}
-
-template<State targetState, EntityType targetType>
-pro_maat::GridPos Rule<targetState, targetType>::getTarget() const
-{
-    return entity.getTarget();
-}
-
-template<State targetState, EntityType targetType>
-const pro_maat::GridPos Rule<targetState, targetType>::getPosition() const
-{
-    return entity.getPosition();
-}
-
-template<State targetState, EntityType targetType>
-const std::vector<pro_maat::GridPos> Rule<targetState, targetType>::getOccupiedSquares() const
-{
-    return entity.getOccupiedSquares();
-}
-
-
 #endif //PROJECT_MAAT_RULES_H