public class LevelHandler {

    @SubscribeEvent
    public void onEntityConstructing(EntityConstructing event)
    {
        if(event.entity instanceof EntityPlayer && ExtendedPlayerProperties.fetchProperties((EntityPlayer)event.entity) == null)
        {
            ExtendedPlayerProperties.register((EntityPlayer)event.entity);
        }
    }

    @SubscribeEvent
    public void onEntityDeath(LivingDeathEvent event)
    {

        System.out.println("test");
        Entity entity = event.entity;
        DamageSource sauce = event.source;

        if(sauce.getSourceOfDamage() instanceof EntityPlayer)
        {

            System.out.println("test2");

            if(ExtendedPlayerProperties.fetchProperties((EntityPlayer)sauce.getSourceOfDamage()) != null)
            {
                ExtendedPlayerProperties playerProperties = new ExtendedPlayerProperties((EntityPlayer)sauce.getSourceOfDamage());

                double mobHP = ((EntityLivingBase)event.entity).getEntityAttribute(SharedMonsterAttributes.maxHealth).getBaseValue();

                int expValue = (int)(((int)mobHP*10)/(playerProperties.getLevel()*5));

                System.out.println("Adding EXP value: "+expValue);

                playerProperties.addExp(expValue);
            }
        }
    }

}