diff --git a/src/world/Action/Action.cpp b/src/world/Action/Action.cpp
index a6478379..b350df8d 100644
--- a/src/world/Action/Action.cpp
+++ b/src/world/Action/Action.cpp
@@ -266,6 +266,13 @@ void Sapphire::Action::Action::execute()
 {
   assert( m_pSource );
 
+  // subtract costs first, if somehow the caster stops meeting those requirements cancel the cast
+  if( !casterHasCostRequirements( true ) )
+  {
+    interrupt();
+    return;
+  }
+
   auto pScriptMgr = m_pFw->get< Scripting::ScriptMgr >();
 
   if( hasCastTime() )
@@ -398,9 +405,8 @@ bool Sapphire::Action::Action::playerPrecheck( Entity::Player& player )
   // validate range
 
 
-  // todo: validate costs/conditionals here
-
-  calculateActionCost();
+  if( !casterHasCostRequirements() )
+    return false;
 
   return true;
 }
@@ -425,4 +431,58 @@ bool Sapphire::Action::Action::isComboAction() const
   }
 
   return m_actionData->actionCombo == lastActionId;
+}
+
+bool Sapphire::Action::Action::casterHasCostRequirements( bool subtractCosts )
+{
+  return primaryCostCheck( subtractCosts ) && secondaryCostCheck( subtractCosts );
+}
+
+bool Sapphire::Action::Action::primaryCostCheck( bool subtractCosts )
+{
+  switch( m_primaryCostType )
+  {
+    case Common::ActionPrimaryCostType::TacticsPoints:
+    {
+      auto curTp = m_pSource->getTp();
+
+      if( curTp < m_primaryCost )
+        return false;
+
+      if( subtractCosts )
+        m_pSource->setTp( curTp - m_primaryCost );
+
+      return true;
+    }
+
+    case Common::ActionPrimaryCostType::MagicPoints:
+    {
+      auto curMp = m_pSource->getMp();
+
+      auto cost = Math::CalcStats::calculateMpCost( *m_pSource, m_primaryCost );
+
+      if( curMp < cost )
+        return false;
+
+      if( subtractCosts )
+        m_pSource->setMp( curMp - cost );
+
+      return true;
+    }
+
+      // free casts, likely just pure ogcds
+    case Common::ActionPrimaryCostType::None:
+    {
+      return true;
+    }
+
+    default:
+      return false;
+  }
+}
+
+bool Sapphire::Action::Action::secondaryCostCheck( bool subtractCosts )
+{
+  // todo: these need to be mapped
+  return true;
 }
\ No newline at end of file
diff --git a/src/world/Action/Action.h b/src/world/Action/Action.h
index d1499c31..216e1b21 100644
--- a/src/world/Action/Action.h
+++ b/src/world/Action/Action.h
@@ -47,6 +47,13 @@ namespace Sapphire::Action
 
     bool isComboAction() const;
 
+    /*!
+     * @brief Checks whether the source chara has the required stats/debuffs/etc to cast an action.
+     * @param subtractCosts Whether we should subtract the costs (eg, mp/tp) from the player or to just check them
+     * @return whether the requirements are met by the caster
+     */
+    bool casterHasCostRequirements( bool subtractCosts = false );
+
     /*!
      * @brief Checks if the action *may* target a resident instead of an actor
      * @return true if the target *may* be a resident and not an actor, otherwise false.
@@ -91,7 +98,9 @@ namespace Sapphire::Action
   protected:
 
     void calculateActionCost();
-    void calculateMPCost( uint16_t baseCost );
+
+    bool primaryCostCheck( bool subtractCosts );
+    bool secondaryCostCheck( bool subtractCosts );
 
     bool playerPrecheck( Entity::Player& player );
 
diff --git a/src/world/Actor/Chara.cpp b/src/world/Actor/Chara.cpp
index 0250e005..fa9724bb 100644
--- a/src/world/Actor/Chara.cpp
+++ b/src/world/Actor/Chara.cpp
@@ -181,6 +181,13 @@ void Sapphire::Entity::Chara::setGp( uint32_t gp )
   sendStatusUpdate();
 }
 
+/*! \param tp amount to set*/
+void Sapphire::Entity::Chara::setTp( uint32_t tp )
+{
+  m_tp = tp;
+  sendStatusUpdate();
+}
+
 /*! \param type invincibility type to set */
 void Sapphire::Entity::Chara::setInvincibilityType( Common::InvincibilityType type )
 {
diff --git a/src/world/Actor/Chara.h b/src/world/Actor/Chara.h
index 97acfa09..00b3148a 100644
--- a/src/world/Actor/Chara.h
+++ b/src/world/Actor/Chara.h
@@ -217,6 +217,8 @@ namespace Sapphire::Entity
 
     void setGp( uint32_t gp );
 
+    void setTp( uint32_t tp );
+
     void setInvincibilityType( Common::InvincibilityType type );
 
     void die();