"This is not your grave... but you are welcome in it." - Closing sentence, said on Regret.
"I? I am a monument to all your sins." - Introducing himself, said on Gravemind.
"This one is machine and nerve, and has its mind concluded. This one is but flesh and faith, and is the more deluded." - Said about John-117 and then Thel 'Vadam, respectively, on Gravemind.
"There is much talk, and I have listened, through rock and metal and time. Now I shall talk, and you shall listen." - Said on Gravemind.
"This one's containment... (gestures to 2401 Penitent Tangent and growls and shudders a bit)... and this one's Great Journey... (gestures to the Prophet of Regret)... are the same. Your Prophets have promised you freedom from a doomed existence, but you will find no salvation on this Ring. Those who built this place knew what they wrought. Do not mistake their intent, or all will perish as they did before." - Said on Gravemind.
"If you will not hear the truth, then I will show it to you. There is still time to stop the key from turning, but first, it must be found. (gestures to John-117) You will search one likely spot... (gestures to Thel 'Vadam)... and you will search another. Fate had us meet as foes, but this Ring will make us brothers." - Said on Gravemind.
"Arrogant creatures! Your deaths will be instantaneous, while we shall suffer the progress of infinitude!" - Said on High Charity.
"We exist together now, two corpses in one grave..." - Said on High Charity.
"Silence fills the empty grave, now that I have gone. But my mind is not at rest, for questions linger on. I will ask, and you will answer." - To Cortana, after Halo 2's credits.
"Do not be afraid. I am peace; I am salvation." - Said on Floodgate.
"I am a timeless chorus. Join your voice with mine, and sing victory everlasting." - Said on Floodgate.
"Do not shoot, but listen! Let me lead you safely... to our foe. Only you can halt... what he has set in motion." - Said through two Tank Forms on The Covenant (referring to the activation of the Halo Array).
"Lies for the weak! Beacons for the deluded!" - Said through the infected Prophet of Truth on The Covenant.
"You will be food; nothing more..." - Said on The Covenant through the Prophet of Truth.
"Now the gate has been unlatched, headstones pushed aside; corpses shift and offer room, a fate you must abide!" - Said on The Covenant.
"Child of my enemy, why have you come? I offer no forgiveness, a father's sins, passed to his son." - Said on Cortana.
"Of course, you came for her. We exist together now, two corpses in one grave." - Said on Cortana.
"And yet, perhaps a part of her remains..."- Said on Cortana.
"Time... has taught me patience! But basking in new freedom, I will know all that I possess!" - Said on Cortana.
"Submit! End her torment and my own!" - Said on Cortana.
"You will show me what she hides! Or I shall feast upon your BONES!" - Said on Cortana.
"(Flood Roar) Now... at last, I see.... Her secret is revealed!!" - Said on Cortana (referring to the Index that Cortana possesses).
"I have beaten fleets of thousands! Consumed a galaxy of flesh and mind and bone!" - Said on Halo.
"Do I take life or give it? Who is victim, and who is foe?" - Said on Halo.
"Resignation is my virtue; like water I ebb, and flow. Defeat is simply the addition of time to a sentence I never deserved... but you imposed." - Said on Halo.
"From end to end of this galaxy, most are blinded!" - Speaking through a Combat Form on Halo.
"No skill." - Speaking through a Combat Form. IWHBYDskull needed.
"You suck!" - Speaking through a Combat Form. IWHBYD skull needed.
"I see you!" - Speaking through a Combat Form. IWHBYD skull needed.
"Ahh... The Armored Casket." - Speaking through a Combat Form.
"Let us begin." - Speaking through a Combat Form.
"There you are!" - If you hide during combat.
"Are you recovered?" - Said through a Combat Form when you have hid for a while.
"Side by side we march as one. Humans and Elites will die. The Earth will fall if we strike together. And so forth shall all of life." Note: Gravemind only seems to be saying this if you play the song Gravemind or Dread Intrusion . If you play the music backwards, and speed it up a little, you can hear some of the lines.
"Fresh Meat!"- Spoken through a Combat Form.
"My food!"- Spoken through a Combat Form.
"Come, we owe him a casket." - Spoken through a Combat Form.
"Ashes to ashes, dust to dust." - Spoken through a Combat Form.
"The armored casket" - Spoken through a combat form.
"I will rise again." - Spoken through a combat form.