We consider the C1-open set $$\cal{V}$$ of partially hyperbolic diffeomorphisms on space $$\mathbb{T}^{2}\times\mathbb{T}^{2}$$ whose non-wandering is not stable, introduced by M. Shub in [57]. Firstly, we show that each diffeormorphism a limit horseshoes sense entropy. Afterwards, establish existence C2-open $$\cal{U}$$ C2-diffeomorphisms and C2-residual subset ℜ such any diffeomorphism has eq...