Revelation 14
9 And the third angel followed them, saying with a loud voice, If any man worship the beast and his image, and receive his mark in his forehead, or in his hand,
10 The same shall drink of the wine of the wrath of God, which is poured out without mixture into the cup of his indignation; and he shall be tormented with fire and brimstone in the presence of the holy angels, and in the presence of the Lamb:
11 And the smoke of their torment ascendeth up for ever and ever: and they have no rest day nor night, who worship the beast and his image, and whosoever receiveth the mark of his name.
Yep, it's eternal torment. Jesus says those that go to hell will burn in fire that shall NOT be quenched into everlasting punishment
Matthew 13:41,42
The Son of man shall send forth his angels, and they shall gather out of his kingdom all things that offend, and them which do iniquity;
And shall cast them into a furnace of fire: there shall be wailing and gnashing of teeth.
Mark 9:43-44
And if thy hand offend thee, cut it off: it is better for thee to enter into life maimed, than having two hands to go into hell, into the fire that never shall be quenched: where their worm dieth not, and the fire is not quenched.
Matthew 25:41
Then shall he say also unto them on the left hand, Depart from me, ye cursed, into everlasting fire, prepared for the devil and his angels:
Matthew 25:46
And these shall go away into everlasting punishment: but the righteous into life eternal.
John 5:29
And shall come forth; they that have done good, unto the resurrection of life; and they that have done evil, unto the resurrection of damnation.
2 Thessalonians 1:9
Who shall be punished with everlasting destruction from the presence of the Lord, and from the glory of his power;
Texts like Jude 6, Matthew 8:12, Matthew 22:13, and Matthew 25:30, and 2 Thessalonians 1:9 show that darkness signifies a state of deprivation and distress, not of destruction in the sense of ceasing to exist. Only those who exist can weep and gnash their teeth, as those banished into the darkness are said to do. Luke 16:22–24 shows that fire signifies continued existence in pain as Revelation 14:10 with 19:20 and 20:10, and Matthew 13:42, 50, confirm this.
Another good case against annihilationism is ”And the smoke of their torment rises forever and ever” in Rev. 14:11.