diff --git a/Java-Knight/src/main/java/org/project/entity/Entity.java b/Java-Knight/src/main/java/org/project/entity/Entity.java
index d8a57fa..3d945a8 100644
--- a/Java-Knight/src/main/java/org/project/entity/Entity.java
+++ b/Java-Knight/src/main/java/org/project/entity/Entity.java
@@ -1,32 +1,42 @@
 package org.project.entity;
 
-public interface Entity {
-//    void attack(Entity target);
+public abstract class Entity {
 
+    void takeDamage(int damage){};
 
-    void defend();
+    void specialAbility(Entity target){};
 
-    void heal(int health);
+    void stun(){};
 
-    void fillMana(int mana);
+    public abstract void stun(boolean value);
 
-    void takeDamage(int damage);
+    void makeCritical(boolean value){};
 
-    void specialAbility(Entity target);
+    boolean isStunned(){};
 
-    void stun();
+    public abstract void setHp(int newHp);
 
-    int getMaxHP();
+    boolean isCritical(){};
 
-    int getMaxMP();
+    public abstract boolean isCritical();
 
-    boolean isStunned();
+    public abstract boolean isStunned();
 
-    void stun(boolean value);
+    boolean isDead(){};
 
+    public abstract void makeCritical(boolean value);
 
+    void makeDie(){};
 
-    /*
-    TODO: ADD OTHER REQUIRED AND BONUS METHODS
-    */
+    public abstract void makeDie();
+
+    void setHp(int hp){};
+
+    public abstract void takeDamage(int damage);
+
+    void stun(boolean value){};
+
+    public abstract boolean isDead();
+
+    public abstract boolean isDead();
 }
diff --git a/Java-Knight/src/main/java/org/project/entity/enemies/Dragon.java b/Java-Knight/src/main/java/org/project/entity/enemies/Dragon.java
index dd23a5c..fd1721f 100644
--- a/Java-Knight/src/main/java/org/project/entity/enemies/Dragon.java
+++ b/Java-Knight/src/main/java/org/project/entity/enemies/Dragon.java
@@ -1,4 +1,22 @@
 package org.project.entity.enemies;
 
+import org.project.entity.Entity;
+import org.project.entity.players.Player;
+import org.project.item.weapons.Weapon;
+
 public class Dragon extends Enemy{
+
+    public Dragon(int hp, Weapon weapon){
+        super(hp, weapon);
+    }
+
+    @Override
+    public void specialAbility(Entity target) {
+        Player targetPlayer = (Player)target;
+        if (targetPlayer.isDefending()){
+            targetPlayer.breakShield();
+        }
+
+        super.attack(targetPlayer);
+    }
 }
diff --git a/Java-Knight/src/main/java/org/project/entity/enemies/Enemy.java b/Java-Knight/src/main/java/org/project/entity/enemies/Enemy.java
index f3f6fcb..45f7274 100644
--- a/Java-Knight/src/main/java/org/project/entity/enemies/Enemy.java
+++ b/Java-Knight/src/main/java/org/project/entity/enemies/Enemy.java
@@ -3,20 +3,30 @@ package org.project.entity.enemies;
 import org.project.entity.Entity;
 import org.project.item.weapons.Weapon;
 
-// TODO: UPDATE IMPLEMENTATION
 public abstract class Enemy implements Entity {
     Weapon weapon;
     private int hp;
-    private int mp;
     private boolean stunned = false;
+    private boolean critical = false;
+    private boolean dead = false;
 
-    public Enemy(int hp, int mp, Weapon weapon) {
+    private static final double DAMAGE_MODIFIER = 1.5; // Used for critical hits
+
+    public Enemy(int hp, Weapon weapon) {
         this.hp = hp;
-        this.mp = mp;
-
         this.weapon = weapon;
     }
 
+    public void attack(Entity target){
+        if (critical){
+            target.takeDamage((int)(weapon.getDamage() * DAMAGE_MODIFIER));
+        }
+        else {
+            target.takeDamage(weapon.getDamage());
+        }
+    }
+
+
     @Override
     public void takeDamage(int damage) {
         hp -= damage;
@@ -27,20 +37,41 @@ public abstract class Enemy implements Entity {
         stunned = value;
     }
 
+    @Override
+    public void makeCritical(boolean value) {
+        critical = value;
+    }
+
+    @Override
+    public void makeDie() {
+        dead = true;
+    }
+
+    @Override
+    public void setHp(int newHp) {
+        hp = newHp;
+    }
+
+    @Override
+    public boolean isCritical(){ return critical;}
+
     @Override
     public boolean isStunned() {
         return stunned;
     }
 
+    @Override
+    public boolean isDead() {
+        return dead;
+    }
+
     public int getHp() {
         return hp;
     }
 
-    public int getMp() {
-        return mp;
-    }
-
     public Weapon getWeapon() {
         return weapon;
     }
+
+    public abstract void specialAbility(Entity target);
 }
diff --git a/Java-Knight/src/main/java/org/project/entity/enemies/Goblin.java b/Java-Knight/src/main/java/org/project/entity/enemies/Goblin.java
index 02aa9f0..c655cde 100644
--- a/Java-Knight/src/main/java/org/project/entity/enemies/Goblin.java
+++ b/Java-Knight/src/main/java/org/project/entity/enemies/Goblin.java
@@ -1,4 +1,33 @@
 package org.project.entity.enemies;
 
+import java.util.Random;
+
+import org.project.entity.Entity;
+import org.project.item.weapons.Weapon;
+
 public class Goblin extends Enemy{
+
+    private static final Random random = new Random();
+    private static final int HEALTH_POINT = 100;
+
+    public Goblin(int mp, Weapon weapon){
+        super(HEALTH_POINT, weapon);
+    }
+
+    @Override
+    public void specialAbility(Entity target) {
+        this.criticality();
+        super.attack(target);
+    }
+
+    // makes the next move critical with a probability of 80
+    private void criticality(){
+        int randNum = random.nextInt(100);
+        if (randNum < 80){
+            this.makeCritical(true);
+        }
+    }
+
+
+
 }
diff --git a/Java-Knight/src/main/java/org/project/entity/enemies/Skeleton.java b/Java-Knight/src/main/java/org/project/entity/enemies/Skeleton.java
index 8a6a555..7d08a76 100644
--- a/Java-Knight/src/main/java/org/project/entity/enemies/Skeleton.java
+++ b/Java-Knight/src/main/java/org/project/entity/enemies/Skeleton.java
@@ -1,6 +1,25 @@
 package org.project.entity.enemies;
 
-// TODO: UPDATE IMPLEMENTATION
-public class Skeleton {
-    // TODO: DESIGN ENEMY AND IMPLEMENT THE CONSTRUCTOR
+import org.project.item.weapons.Weapon;
+
+public class Skeleton extends Enemy {
+
+    private int deathCounter = 0;
+    private int initialHp;
+
+    public Skeleton(int hp, Weapon weapon){
+        super(hp,weapon);
+        initialHp = hp;
+    }
+
+    @Override
+    public void makeDie() {
+        if (deathCounter == 0){
+            this.setHp(initialHp / 2);
+            deathCounter++;
+            return;
+        }
+
+        super.makeDie();
+    }
 }
diff --git a/Java-Knight/src/main/java/org/project/entity/enemies/Vampire.java b/Java-Knight/src/main/java/org/project/entity/enemies/Vampire.java
index f2323fb..82bd9ac 100644
--- a/Java-Knight/src/main/java/org/project/entity/enemies/Vampire.java
+++ b/Java-Knight/src/main/java/org/project/entity/enemies/Vampire.java
@@ -1,4 +1,21 @@
 package org.project.entity.enemies;
 
+import org.project.entity.Entity;
+import org.project.item.weapons.Weapon;
+
 public class Vampire extends Enemy{
+
+    private static final int SPECIAL_ABL_DMG = 40;
+    private static final int RANDEMANT_PERCENT = 70; // this constant determines how much of dealt damage should be given to vamp.
+
+    public Vampire(int hp, Weapon weapon){
+        super(hp, weapon);
+    }
+
+    @Override
+    public void specialAbility(Entity target) {
+        System.out.println("Stealing life!...");
+        target.takeDamage(SPECIAL_ABL_DMG);
+        this.heal((SPECIAL_ABL_DMG * RANDEMANT_PERCENT) / 100);
+    }
 }
diff --git a/Java-Knight/src/main/java/org/project/entity/players/Knight.java b/Java-Knight/src/main/java/org/project/entity/players/Knight.java
index ee2c846..18cdc12 100644
--- a/Java-Knight/src/main/java/org/project/entity/players/Knight.java
+++ b/Java-Knight/src/main/java/org/project/entity/players/Knight.java
@@ -14,6 +14,8 @@ public class Knight extends Player {
     @Override
     public void specialAbility(Entity target) {
         System.out.println("Performing shield bash...");
+
+
         target.stun(true);
         target.takeDamage(50);
     }
diff --git a/Java-Knight/src/main/java/org/project/entity/players/Player.java b/Java-Knight/src/main/java/org/project/entity/players/Player.java
index df7615e..273ff7f 100644
--- a/Java-Knight/src/main/java/org/project/entity/players/Player.java
+++ b/Java-Knight/src/main/java/org/project/entity/players/Player.java
@@ -4,7 +4,6 @@ import org.project.entity.Entity;
 import org.project.item.armors.Armor;
 import org.project.item.weapons.Weapon;
 
-// TODO: UPDATE IMPLEMENTATION
 public abstract class Player implements Entity {
     protected String name;
     Weapon weapon;
@@ -14,7 +13,14 @@ public abstract class Player implements Entity {
     private int mp;
     private int maxMP;
     private boolean isDefending = false;
-    private boolean stunned;
+    private boolean stunned = false;
+    private boolean critical = false;
+    private boolean dead = false;
+
+    private static final double DAMAGE_MODIFIER = 1.5; // Used for critical hits
+    private static final int LIGHT_ATTACK_DAMAGE = 10;
+    private static final int DEFEND_MP_COST = 5;
+    private static final int HEAL_MP_COST = 10;
 
     public Player(String name, int hp, int mp, Weapon weapon, Armor armor,int maxHP, int maxMP) {
         this.name = name;
@@ -29,21 +35,37 @@ public abstract class Player implements Entity {
     }
 
     public void lightAttack(Entity target){
-        target.takeDamage(10);
+        if (critical){
+            target.takeDamage((int)(LIGHT_ATTACK_DAMAGE*DAMAGE_MODIFIER));
+            this.makeCritical(false);
+        }
+        else {
+            target.takeDamage(LIGHT_ATTACK_DAMAGE);
+        }
     }
 
     public void heavyAttack(Entity target){
-        target.takeDamage(weapon.getDamage());
+        if (critical){
+            target.takeDamage((int)(weapon.getDamage()*DAMAGE_MODIFIER));
+        }
+        else {
+            target.takeDamage(weapon.getDamage());
+        }
         mp -= weapon.getManaCost();
     }
 
-    @Override
     public void defend() {
-        this.mp -= 5;
+        this.mp -= DEFEND_MP_COST;
         isDefending = true;
         System.out.println("Defending...");
     }
 
+    public void breakShield(){ // used for dragon ability
+        if (isDefending){
+            isDefending = false;
+        }
+    }
+
 
     @Override
     public void takeDamage(int damage) {
@@ -57,33 +79,34 @@ public abstract class Player implements Entity {
 
     }
 
-    @Override
     public void heal(int health) {
-        mp -= 10;
+        mp -= HEAL_MP_COST;
         hp += health;
         if (hp > maxHP) {
             hp = maxHP;
         }
     }
 
-    @Override
     public void fillMana(int mana) {
         mp += mana;
         if (mp > maxMP) {
             mp = maxMP;
         }
     }
-
+    
     @Override
-    public void stun() {
-        stunned = true;
+    public void makeCritical(boolean value) {
+        critical = value;
     }
 
     @Override
-    public boolean isStunned() {
-        return stunned;
+    public void makeDie() {
+        dead = true;
     }
 
+    @Override
+    public boolean isCritical(){ return critical;}
+
     public String getName() {
         return name;
     }
@@ -92,7 +115,15 @@ public abstract class Player implements Entity {
         return hp;
     }
 
+    public boolean isDefending() {
+        return isDefending;
+    }
+
     @Override
+    public boolean isDead() {
+        return dead;
+    }
+
     public int getMaxHP() {
         return maxHP;
     }
@@ -101,11 +132,6 @@ public abstract class Player implements Entity {
         return mp;
     }
 
-    @Override
-    public int getMaxMP() {
-        return maxMP;
-    }
-
     public Weapon getWeapon() {
         return weapon;
     }
diff --git a/Java-Knight/src/main/java/org/project/item/weapons/Sword.java b/Java-Knight/src/main/java/org/project/item/weapons/Sword.java
index 8c7be6a..bfe3eef 100644
--- a/Java-Knight/src/main/java/org/project/item/weapons/Sword.java
+++ b/Java-Knight/src/main/java/org/project/item/weapons/Sword.java
@@ -6,21 +6,12 @@ import java.util.ArrayList;
 
 // TODO: UPDATE IMPLEMENTATION
 public class Sword extends Weapon {
-    /*
-    THIS IS AN EXAMPLE OF A WEAPON DESIGN.
-    */
 
-    int abilityCharge;
+    private static final int DAMAGE = 50;
+    private static final int MANA_COST
 
-    public Sword() {
-        // TODO: DESIGN SWORD'S ATTRIBUTES IMPLEMENT THE CONSTRUCTOR
+    public Sword(int damage, int manaCost) {
+        super(damage, manaCost);
     }
 
-    // TODO: (BONUS) UPDATE THE UNIQUE ABILITY
-    public void uniqueAbility(ArrayList<Entity> targets) {
-        abilityCharge += 2;
-        for (Entity target : targets) {
-            target.takeDamage(getDamage());
-        }
-    }
 }
diff --git a/Java-Knight/src/main/java/org/project/item/weapons/Weapon.java b/Java-Knight/src/main/java/org/project/item/weapons/Weapon.java
index cb9fcf2..a106d15 100644
--- a/Java-Knight/src/main/java/org/project/item/weapons/Weapon.java
+++ b/Java-Knight/src/main/java/org/project/item/weapons/Weapon.java
@@ -2,15 +2,10 @@ package org.project.item.weapons;
 
 import org.project.entity.Entity;
 
-// TODO: UPDATE IMPLEMENTATION
 public abstract class Weapon {
     private int damage;
     private int manaCost;
 
-    /*
-    TODO: ADD OTHER REQUIRED AND BONUS ATTRIBUTES
-    */
-
     public Weapon(int damage, int manaCost) {
         this.damage = damage;
         this.manaCost = manaCost;
@@ -28,8 +23,4 @@ public abstract class Weapon {
     public int getManaCost() {
         return manaCost;
     }
-
-    /*
-    TODO: ADD OTHER REQUIRED AND BONUS METHODS
-    */
 }