- The Forward Unto Dawn is still in its H3 form.
- Halo 4 Charon-class frigates are a redesign of the ship class by the Navy after 2552.
- Chief's underarmor doesn't look quite as futuristic as it does in Halo 4.
- The new UNSC symbol is only on newer ships
- Every Covenant variation across the games represents a different subspecies, much as humans have different races, and outside of the games all varieties can be seen together

That last one especially. It kills me really all the backlash against some of the visual differences. The Dawn change? That's dumb. But more variations in how a species looks? That's fine, really. And they really aren't all that far off. I've always wished I had the time and talent to create a species board for each faction and include all the variations using a baseline art style to show just how much more realistic it is to actually have lots of looks within a specific group of alien lifeforms.

I feel the same way about vehicles. The Banshee is always my fallback argument; the Reach/H4 style and the H2/3/ODST style are equally canon. You would see both in the "real world". In fact, I'm convinced that Jeremy (Vociferous) put in that caveat in the Banshee entry in the Essential Visual Guide based on my many back and forths with him on the subject, lol. Same with variations of Pelicans, Warthogs, etc.

Armor as well. I actually like a lot of the H4 armor, so everyone else can suck it lol. And just because I don't like the way it might look doesn't mean it;s not canon. Something like Hayabusa has a story bit that goes along with it. It's canon. Don't like it? Tough lol. Do I like the way Defender and Bionicle - I mean Ranger - look in H4? No, I think they look stupid, but they're still canon. Not a huge fan of Pioneer, but I love the idea of S-IV's wearing them down exploring 03. Every little piece of armor, every map description, they all add to the universe in a wonderful way. Makes it all feel that much more realistic to me.

Halo: Fistful of Arrows? Hell yeah that's canon. Which means so am I. ;-)

And as far as I'm concerned, every bit of released fictional property is canon unless it's a ridiculous contradiction, and then I'll decide which I like better. Hell, a bunch of "actual" human history is retconned, lol.

Grim