I found some ahadith that talk about the torture of the grave and dragons/snakes biting the unbelievers are these hadiths authentic?
Narrated AbuSa'id Allah's Messenger (peace be upon him) said: There dominate NINETY-NINE DRAGONS over the unbeliever in the grave. They (constantly) bite him and sting him till there comes the hour (of resurrection). (These dragons are so poisonous) that if one of them exhales on the Earth, no verdure will ever grow upon it.
Reported by Darimi, Tirmidhi transmitted something similar but he said seventy instead of ninety-nine.
(Al-Tirmidhi, Number 46;
When the Prophet (peace be upon him) went out to the prayer and saw the people looking as if they were grinning he said, "If you were to keep much in remembrance death which is the cutter-off of pleasures, it would distract you from what I see. Keep much in remembrance death which is the cutter-off of pleasure, for a day does not come to the grave without its saying, ‘I am the house of exile, I am the house of solitude, I am the house of dust, I am the house of worms.’ When a believer dies the grave says to him, ‘Welcome and greeting; you are indeed the dearest to me of those who walk upon me. I have been given charge of you today and you have come to me and you will see how I shall treat you.’ It will then expand for him as far as the eye can see and a door to Paradise will be opened for him. But when the profligate or infidel is buried the grave says to him, ‘No welcome and no greeting to you; you are the most hateful to me of those who walk upon me. I have been given charge of you today and you have come to me and you will see how I shall treat you.’ AbuSa'id told that Allah's Messenger indicated it by interlacing his fingers. Then he said, "SEVENTY DRAGONS will be put in charge of him of such a nature that if one of them were to breathe on the earth it would produce no crops as long as the world lasted, and they will bite and scratch him till he is brought to the reckoning." He also reported Allah's Messenger (peace be upon him) as saying. "The grave is one of the gardens of Paradise, or one of the pits of Hell."
Tirmidhi transmitted it.
(Tirmidhi Hadith, Number 1429-