Keys of Death and Hades

Revelation 1:18
I am the Living One; I was dead, and behold I am alive for ever and ever! And I hold the keys of death and Hades.

Other items:

Matthew 16:18
And I tell you that you are Peter, and on this rock I will build my church, and the gates of Hades will not overcome it.

Revelation 6:8
I looked, and there before me was a pale horse! Its rider was named Death, and Hades was following close behind him. They were given power over a fourth of the earth to kill by sword, famine and plague, and by the wild beasts of the earth.

Revelation 20:13
The sea gave up the dead that were in it, and death and Hades gave up the dead that were in them, and each person was judged according to what he had done.

Revelation 20:14
Then death and Hades were thrown into the lake of fire. The lake of fire is the second death.