diff --git a/src/Battling/Flow/TurnHandler.cpp b/src/Battling/Flow/TurnHandler.cpp
index 08b164f..3707530 100644
--- a/src/Battling/Flow/TurnHandler.cpp
+++ b/src/Battling/Flow/TurnHandler.cpp
@@ -103,8 +103,7 @@ void CreatureLib::Battling::TurnHandler::HandleAttackForTarget(CreatureLib::Batt
 
         //HOOK: Change move type
         hit.SetEffectiveness(library->GetTypeLibrary()->GetEffectiveness(hit.GetType(), target->GetTypes()));
-        //TODO: Critical calculation
-        hit.SetCritical(false);
+        hit.SetCritical(library->GetCriticalLibrary()->IsCritical(&attack, target, hitIndex));
         hit.SetBasePower(dmgLibrary->GetBasePower(&attack, target, hitIndex));
         hit.SetDamage(dmgLibrary->GetDamage(&attack, target, hitIndex));
 
diff --git a/src/Battling/Library/BattleLibrary.cpp b/src/Battling/Library/BattleLibrary.cpp
index 5470b61..02f8a31 100644
--- a/src/Battling/Library/BattleLibrary.cpp
+++ b/src/Battling/Library/BattleLibrary.cpp
@@ -1,14 +1,18 @@
 #include "BattleLibrary.hpp"
 
 CreatureLib::Battling::BattleLibrary::BattleLibrary(CreatureLib::Library::DataLibrary *staticLib,
-                                                    CreatureLib::Battling::BattleStatCalculator *statCalculator)
-                                                    : _staticLib(staticLib), _statCalculator(statCalculator)
+                                                    CreatureLib::Battling::BattleStatCalculator *statCalculator,
+                                                    DamageLibrary* damageLibrary,
+                                                    CriticalLibrary* criticalLibrary)
+                                                    : _staticLib(staticLib), _statCalculator(statCalculator),
+                                                    _damageLibrary(damageLibrary), _criticalLibrary(criticalLibrary)
                                                     {}
 
 CreatureLib::Battling::BattleLibrary::~BattleLibrary() {
     delete _staticLib;
     delete _statCalculator;
     delete _damageLibrary;
+    delete _criticalLibrary;
 }
 
 const CreatureLib::Library::LibrarySettings& CreatureLib::Battling::BattleLibrary::GetSettings() const {
@@ -39,3 +43,7 @@ const CreatureLib::Battling::DamageLibrary *CreatureLib::Battling::BattleLibrary
     return _damageLibrary;
 }
 
+const CreatureLib::Battling::CriticalLibrary *CreatureLib::Battling::BattleLibrary::GetCriticalLibrary() const {
+    return _criticalLibrary;
+}
+
diff --git a/src/Battling/Library/BattleLibrary.hpp b/src/Battling/Library/BattleLibrary.hpp
index aa3aefa..67f2833 100644
--- a/src/Battling/Library/BattleLibrary.hpp
+++ b/src/Battling/Library/BattleLibrary.hpp
@@ -4,14 +4,17 @@
 #include "BattleStatCalculator.hpp"
 #include "../../Library/DataLibrary.hpp"
 #include "DamageLibrary.hpp"
+#include "CriticalLibrary.hpp"
 
 namespace CreatureLib::Battling {
     class BattleLibrary {
         const Library::DataLibrary* _staticLib;
         BattleStatCalculator* _statCalculator;
         DamageLibrary* _damageLibrary;
+        CriticalLibrary* _criticalLibrary;
     public:
-        BattleLibrary(Library::DataLibrary* staticLib, BattleStatCalculator* statCalculator);
+        BattleLibrary(Library::DataLibrary* staticLib, BattleStatCalculator* statCalculator, DamageLibrary* damageLibrary,
+                CriticalLibrary* criticalLibrary);
         ~BattleLibrary();
 
         const Library::LibrarySettings& GetSettings() const;
@@ -22,6 +25,7 @@ namespace CreatureLib::Battling {
 
         const BattleStatCalculator* GetStatCalculator() const;
         const DamageLibrary* GetDamageLibrary() const;
+        const CriticalLibrary* GetCriticalLibrary() const;
     };
 }
 
diff --git a/src/Battling/Library/CriticalLibrary.cpp b/src/Battling/Library/CriticalLibrary.cpp
new file mode 100644
index 0000000..eb82f13
--- /dev/null
+++ b/src/Battling/Library/CriticalLibrary.cpp
@@ -0,0 +1,9 @@
+#include "CriticalLibrary.hpp"
+#include "../Models/Battle.hpp"
+
+bool CreatureLib::Battling::CriticalLibrary::IsCritical(CreatureLib::Battling::ExecutingAttack *attack,
+                                                        CreatureLib::Battling::Creature *target, uint8_t hit) const {
+    auto rand = target->GetBattle()->GetRandom();
+    //HOOK: Increase chance for critical hits.
+    return rand.Get(10) <= 0;
+}
diff --git a/src/Battling/Library/CriticalLibrary.hpp b/src/Battling/Library/CriticalLibrary.hpp
new file mode 100644
index 0000000..63406b1
--- /dev/null
+++ b/src/Battling/Library/CriticalLibrary.hpp
@@ -0,0 +1,14 @@
+#ifndef CREATURELIB_CRITICALLIBRARY_HPP
+#define CREATURELIB_CRITICALLIBRARY_HPP
+
+#include "../Models/ExecutingAttack.hpp"
+
+namespace CreatureLib::Battling {
+    class CriticalLibrary {
+    public:
+        virtual bool IsCritical(ExecutingAttack* attack, Creature* target, uint8_t hit) const;
+    };
+}
+
+
+#endif //CREATURELIB_CRITICALLIBRARY_HPP
diff --git a/tests/TestLibrary/TestLibrary.cpp b/tests/TestLibrary/TestLibrary.cpp
index 7443cf2..9e9c4f8 100644
--- a/tests/TestLibrary/TestLibrary.cpp
+++ b/tests/TestLibrary/TestLibrary.cpp
@@ -52,7 +52,8 @@ static TypeLibrary* BuildTypeLibrary(){
 static BattleLibrary* BuildLibrary(){
     auto l = new DataLibrary(LibrarySettings(100, 4), BuildSpeciesLibrary(), BuildAttackLibrary(),
             BuildItemLibrary(), BuildGrowthRateLibrary(), BuildTypeLibrary());
-    auto battleLib = new BattleLibrary(l, new BattleStatCalculator());
+    auto battleLib = new BattleLibrary(l, new BattleStatCalculator(), new DamageLibrary(),
+            new CriticalLibrary());
     return battleLib;
 }