Lord Krishna says, ‘Among the Rudras I am Lord Shiva’.
In the next verse He says, 'Purodhasam cha mukhyam mam viddhi partha brhaspatim. Senaninam aham skandah sarasam asmi sagarah'. (10.24)
Lord Krishna says, ‘Among the generals of war, I am Lord Kartikeya’.
So Lord Krishna and Lord Shiva are the same. There is no difference.