1.When the fusion material in a star takes more energy to fuse than it gives by fusion, the radiation pressure falls. After a certain point (depending on the mass of the star), the star will not be able to balance radiation pressure and gravitational pressure, so it collapses. If it is fairly average like our sun, it won't fall below any other outward pressure, so it would form a white dwarf. If the mass is high enough like a giant or supergiant, it passes the electron-degeneracy pressure and forms a neutron star. If it is a high-mass supermassive star, it will go past neutron degeneracy pressure and form a black hole. Depending on the state of the star at hyper/supernova (which are the only novae that form black holes), it will be spinning/not and have a charge/not. 2. Hyper novae. Don't get close ;)