Hello I was looking unsuccesfully weather there is in dots or havoc support for soft body and hydrodynamics (sth like in http://obi.virtualmethodstudio.com/index.html), is there? Or particle physics like nvidia flex? Thanks for help
Nope, that's not what havok or unity physics are. They are rigidbody solvers in the vain of PhysX. Obi and other soft body solvers are generally based on position based dynamics solvers. Which while cool, tend to be less useful for gameplay due to their relatively high cost per object. That said i do hope unity has something planned for handling cloth simulation, my characters will need dangly bits after all.
Something that surprised us what people did with rigid body solver (and I suppose some contact modifiers and penetration recovery) https://www.reddit.com/r/Unity3D/comments/i5o11r/softbody_wheel_collider_using_ecs_and_havok/