Terminal/Halo 3/Five

After getting a Hornet, fly towards the second tower (the one that the Elites have already disabled). The Arbiter will remind you that Tower 2 is already clear, just to confirm you are at the right place. The Terminal is in the main hallway of the structure, with three dead elites, opposite from the only (locked) door. (And as a bonus, there is a skull on the outside of Tower 2 on the rise platform in the middle; just walk up and claim it for another achievement. Note that the skull won't be present if you start from Rally Point Alpha, or are playing on the Easy difficulty.)
 * Walkthrough :

Considering the enemy compound intelligence's raw [computing] power the Key-ships strategy will only remain viable for another [657,000 hours] and this current stalemate has the potential to last considerably longer than that.

With my understanding of the enemy's [modus operandi], its logical boundaries, and [catalog of witness] I have devised what I believe is our most sound fall-back strategy.

By [cutting fire breaks[?]] into the [core worlds' volume] we would be able to frustrate the enemy's advances for approximately [70,080 hours] and lure them into costly naval battles.

While its resources on the ground are effectively limitless, it has a finite number of vessels to spread from system to system. Fortunately the majority of them are unarmed and unarmored, private and commercial craft.

If we start immediately - commence total biosphere elimination of life sustaining worlds (as indicated in the accompanying charts) and relocate evacuated populations to facilities such as those described in the [Onyx project] - all this could be achieved in [571,590 (+- 2,184) hours].

(Upon shutdown, from Mendicant Bias: "The daemons are not taking a kind view of your presence here. They don't want me speaking to you.")

(The following appears only if you access the Terminal on Easy difficulty)

(Upon being rerouted to a new destination within Terminal)

I render judgment on you; you who would obstruct destiny. Doing so brings me no joy; it is necessity that compels me.

Understand this: the Mantle you have shouldered I do rescind - with far more consideration than it was granted.

[retf-2.4.z] Contender [AI] 05-032 confirmed rampant. . . [35:52:75:23:64] _ xx01-83-244.53

(The following appears only if you access the Terminal on Normal difficulty)

(Upon being rerouted to a new destination within Terminal)

I kill you all and I enjoy it. I destroy you in your indolent billions - in your gluttony, in your self-righteousness, in you arrogance. I pound your cities into dust; turn back the clock on your civilization's progress. What has taken you millennia to achieve I erase in seconds.

Welcome back to the [Stone Age] , vermin. Welcome home.

[retf-2.4.z] Contender [AI] 05-032 confirmed rampant. . . [35:52:75:23:64] _ xx01-83-244.53

(The following appears only if you access the Terminal on Heroic difficulty)

(Upon being rerouted to a new destination within Terminal)

You are an impediment that the universe can no longer abide. Nature itself cries out for your destruction and I am its willing instrument. I will hammer your cities until no stone lies atop another. I will drive your people back into the caves they never should have left.

Your civilization has seen its final days. You will know your place.

[retf-2.4.z] Contender [AI] 05-032 confirmed rampant. . . [35:52:75:23:64] _ xx01-83-244.53

(The following appears only if you access the Terminal on Legendary difficulty)

(Upon being rerouted to a new destination within Terminal)

Your history is an appalling chronicle of overindulgence and self-appointed authority. You have spent millennia [navel-gazing] while the universe has continued to evolve. And now you claim the Mantle is justification for impeding nature's inevitable refinement?

You are deluded. But through death you will transcend ignorance.

[retf-2.4.z] Contender [AI] 05-032 confirmed rampant. . . [35:52:75:23:64] _ xx01-83-244.53