Dear 343,
Happy Birthday for Halo 5! I thought one way to show my appreciation for the Campaign story and secrets was to pick a few highlights out…
It turned out I only bought the first time I asked! In tasks as Boolean as they were Herculean, I have “seen the light (ring)”! So, once I got the Space Elevator offline, and saw where Eagles and AMeZCUA switch places, no wonder Sloane was polite again.
Yes, I do CY0, 1234, with my 007-style BD2. But M-00 or 00-M?
I found three chevron pairs, 2C4:5, >> ON, and on an Elite’s left arm. Fortunately, the Valkyrie rode, now the Einherjar awaits Ragnarok to return.
Chief’s last doubt was sublime. Never say a farewell from a mission report or via the other witness. Brings a whole new meaning to the phrase “Cortana’s back!”
I also had some “Memories of Reach”, so it was fun to spot the differentce, and say hello to Kelly before the storm arrived - now where did Palmer park her Pelican?
The Archeon was fun to meet too: loved the Prime Directive reveal scene.
The Goddess of the Hunt’s radar-like pulse surely echoes from the locked doors of that two-faced Saturn. Surely, 'tis Fimbulwinter, and worms creep after dark, but those who over-react tend to poison the whole atmosphere. The writing is on the wall, Truth’s ship rises, Ragnarok approaches and “This is the way the world ends…”
They should have left the sleeping one alone, alas the hieroglyphs upon the Temple wall show rings had previously arisen far away. Alas for prophecy, I have a mortal dread of the world being over-run with an outbreak of “great drownings”, LOL!
But, the best news of Halo 5? When we finally release Agent Moron from Argent Moon, we find that most Boolean of characters, Bastion, still lives!!! YAY! 
So, thank you, all at 343, for all your efforts in writing and creating Halo 5. It was great, lots of secrets, lots of puzzles, and lots of fun to play!
And, yes, well, maybe it did take me long enough… 
Yours,
Abbey 