The Hour will not be established until wild beasts speak to people

It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "By the One in whose Hand is my soul! The Hour will not be established until beasts of prey speak to human beings, and until the tip of a man's whip ('adhabat sawtih) and the strap of his sandal (shirak na'lih) speak to him, and (the strap) informs him of everything that his family did after he left."
This hadith is sahih (authentic) on the condition of Imam Muslim, but the two Shaykhs (Bukhari and Muslim) did not record it.

It is narrated from Sayyiduna Hudhayfah (may Allah be pleased with him) that he said: "If any of you wishes to know whether he has been struck by trial or not, let him look: if he has begun to regard as lawful something he (previously) regarded as unlawful, then he has fallen victim to trial; and if he has begun to regard as unlawful something he (previously) regarded as lawful, then (certainly) trial has engulfed him."
This hadith has an authentic (sahih) chain of narration on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it.

It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that a shepherd was grazing his sheep in the Harrah (the stony tract of Madinah) when suddenly a wolf attacked one of the sheep. The shepherd came between the wolf and the sheep, so the wolf sat back on its tail and said: "O servant of Allah! Are you coming between me and provision that Allah has sent to me?" The man said (in amazement): "How astonishing that a wolf is speaking to me like a human being!" The wolf said: "Shall I not tell you of something even more astonishing than this? The Messenger of Allah (peace and blessings be upon him) is between the two Harrahs (the lava fields of Madinah), informing people of the news of past times." So the shepherd drove his sheep to a corner of Madinah, then came to the Prophet (peace and blessings be upon him) and related the whole incident. The Messenger of Allah (peace and blessings be upon him) came out to the people and said: "He has spoken the truth, by the One in whose Hand is my soul (it is so)."
This hadith is sahih (authentic) on the condition of Imam Muslim, but the two Shaykhs (Bukhari and Muslim) did not record it.

It is narrated from Sayyiduna Abdullah bin Amr bin al-As (may Allah be pleased with them both) that (soon), upon the emergence of some ruler or the rise of some tribe, two groups will fight each other over the slogans of Jahiliyyah (pre-Islamic ignorance). Then the group that prevails will (in reality) be humiliated, and its nearest enemy will covet it (its position), and then they will plunge into the Fire.
This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it.

It is narrated from Sayyiduna Hudhayfah (may Allah be pleased with him) that he said: "A trial is presented to the hearts. Whichever heart rejects it, a white spot is placed in it, and whichever heart does not reject it, a black spot is placed in it. Then another trial is presented to the hearts. If the heart that rejected the first time rejects it (again), a further white spot is placed in it, and the one that does not reject it, a black spot is placed in it. Then a third trial is presented to the hearts. If the one that rejected the first two times rejects it (still), that heart becomes firm, white and pure, and no trial will ever harm it. But if it did not reject the first two times, that heart becomes black, dusky in colour and turned upside down; then it neither recognises any good nor rejects any evil."
This hadith is sahih (authentic) on the condition of the two Shaykhs (Bukhari and Muslim), but they did not record it.