class Bots
{
    public:
      Bots(irr::scene::ISceneManager *mgr) : sceneManager(mgr)
      {
      }
      bool Spawn();
    protected:
      irr::scene::ISceneManager *sceneManager;
};

#include <irrlicht.h>

int main(...
{
       make your device
      irr::scene::ISceneManager *smgr = device->getSceneManager();

      Bots *factory = new Bots(mgr);

      factory->Spawn();

      while(device->run())
      {
           ...
      }

      device->drop();
      delete factory;
}