diff --git a/src/controllers/user.js b/src/controllers/user.js
index 06d51d6554..4731a106c7 100644
--- a/src/controllers/user.js
+++ b/src/controllers/user.js
@@ -302,6 +302,7 @@ api.cast = function(req, res, next) {
   var klass = shared.content.spells.special[req.params.spell] ? 'special' : user.stats.class
   var spell = shared.content.spells[klass][req.params.spell];
   if (!spell) return res.json(404, {err: 'Spell "' + req.params.spell + '" not found.'});
+  if (spell.mana > user.stats.mp) return res.json(400, {err: 'Not enough mana to cast spell'});
 
   var done = function(){
     var err = arguments[0];