I thought to share a quick study that you may like.
In the Hebrew Bible, the prophets use two primary phrases for the end times: be'acharit hayamim ("in the latter/last days") and et ketz ("the time of the end"), alongside "that day" (bayom hahu) and "the Day of the Lord" (yom YHWH).
Jacob / Israel (Genesis 49:1): Gathers his twelve sons to tell them what will befall each tribe in the "last days" (be'acharit hayamim), culminating in the sceptre and lawgiver remaining with Judah until Shiloh (Messiah) comes.
Balaam (Numbers 24:14–19): Explicitly tells Balak what the people of Israel will do to the nations in the "latter days" (be'acharit hayamim), prophesying the Star out of Jacob and Scepter out of Israel that crushes the rebellious nations.
Moses (Deuteronomy 4:30 & 31:29): Foretells that in the "latter days" (be'acharit hayamim), after Israel corrupts itself, falls into severe tribulation, and is scattered among the nations, they will finally return to the Lord their God and obey His voice.
Isaiah (Isaiah 2:2–4, 13:9–13, 24:18–23, 46:10): Uses the exact phrase "in the last days" (2:2) for the final exaltation of the Lord's house after He judges the proud and lofty; describes the foundations of the earth shaking violently while the sun is darkened in its going forth and the moon does not shine (13:10, 24:23).
Jeremiah (Jeremiah 23:20, 30:24, 48:47, 49:39): Repeatedly declares that the fierce anger of the Lord will not turn back until He has executed the intents of His heart, adding the signature promise that in the "latter days" (be'acharit hayamim) you will understand it perfectly—specifically linking it to the time of "Jacob's trouble" (30:7) and the overthrow of Babylon (chapters 50–51).
Ezekiel (Ezekiel 7:2–6, 38:8, 38:16): Declares in chapter 7 that "an end, the end has come upon the four corners of the land," and explicitly places the northern invasion of Gog against the "unwalled villages" of Israel in the "latter years" (be'acharit hashanim, 38:8) and the "latter days" (be'acharit hayamim, 38:16), accompanied by a massive global earthquake that shakes every mountain and wall to the ground (38:19–20).
Daniel (Daniel 2:28, 8:17, 8:19, 10:14, 11:35, 11:40, 12:4, 12:9, 12:13): The most extensive Old Testament prophet of the final timeline. He tells Nebuchadnezzar what will happen in the "latter days" (2:28), receives the angel Gabriel's explanation of what will occur in the "last end of the indignation" (be'acharit haza'am, 8:19) and "latter days" (10:14), and repeatedly anchors the final conflict of the kings of the North and South to "the time of the end" (et ketz, 11:35, 11:40, 12:4, 12:9).
Hosea (Hosea 3:4–5): Prophesies that the children of Israel will abide for many days without a king, prince, or sacrifice, and afterward will return and seek the Lord their God and David their king, coming in reverence to the Lord in the "latter days" (be'acharit hayamim).
Joel (Joel 2:1–2, 2:10, 2:28–31, 3:14–16): Prophesies the outpouring of the Spirit (which the Apostle Peter quotes in Acts 2:17 explicitly as "in the last days"), accompanied by the earth quaking, the heavens trembling, the sun turning into darkness, and the moon into blood before the great and terrible Day of the Lord.
Amos (Amos 8:2, 8:8–9): Announces that "the end (ha-ketz) has come," pairing the final judgment with the land trembling like the rising and falling of the Nile and God causing the sun to go down at noon, darkening the earth in broad daylight.
Micah (Micah 4:1–3): Parallels Isaiah 2:2 word-for-word, declaring what shall come to pass in the "last days" (be'acharit hayamim) after Jerusalem's corrupt human builders see their city plowed like a field (3:12).
Habakkuk (Habakkuk 2:3): Declares that the prophetic vision is yet for an appointed time, and at "the end" (la-ketz) it will speak and not lie—leading into chapter 3's vision of God shaking the earth, splitting the land with rivers, and causing the sun and moon to stand still in their habitation.
Zephaniah (Zephaniah 1:14–18): Describes the great Day of the Lord as a day of wrath, darkness, gloominess, and thick clouds, where the whole land is devoured by the fire of His jealousy and He brings a speedy "end" (kalah) of all who dwell in the land.
Haggai (Haggai 2:6–7, 2:21–22): Promises that in a little while God will "shake the heavens and the earth, the sea and the dry land," overthrowing the throne of kingdoms and destroying the strength of the Gentile kingdoms.
Zechariah (Zechariah 12:2–9, 14:1–9): Details the final siege of Jerusalem ("in that day") when all nations gather against the city, culminating in the Lord's feet standing on the Mount of Olives—triggering a massive earthquake (explicitly compared to the great earthquake in the days of King Uzziah) on a unique day when "there shall not be light; the lights will diminish" (14:5–6).
Malachi (Malachi 4:1–6): Closes the Old Testament canon by describing the final Day of the Lord burning like an oven to consume the proud and wicked, while promising the rising of the Sun of Righteousness and the sending of Elijah the prophet before that great and dreadful day arrives.
