It seems pretty inconsistent throughout the games where exactly the smart-linked scope is attached. In Halo: CE, the M6D's scope is clearly on top, as it is the only attachment. In Halo 3, the M6G has no zoom capability, though it features a mystery attachment on top, bearing the same design as the M6D's scope. This is where it gets interesting. In Halo: Reach, the weapon is the M6G, same as in Halo 3, but now features zoom capability and features both a top and bottom attachment. Since the Halo 3 M6G had this top attachment and did not have zoom capability, it can be implied that this new bottom attachment to the Reach M6G is the scope. Alternatively, you could say the M6G in Halo 3 did have canonical zoom capability and the top attachment really was a scope, but wasn't usable in gameplay, meaning the Halo: Reach M6G's scope is mounted on top as well. In Halo 4, the M6H features this same two-attachment setup and has zoom capability.
There's also the question of what these non-scope attachments are. In Halo lore, all UNSC firearms have devices that smart-link the weapon's aiming information to the user's HUD. This is why there is no need to aim down iron sights, reflex sights, scopes, etc., manually. In Halo 3, it could be theorized that this lone, top-mounted attachment is what smart-links the weapon to the user's HUD, but without magnification. However, the M6C of Halo 2 doesn't have ANY attachments and has smart-linked aiming. The M6G in Halo: Reach and the M6H of Halo 4 both have top and bottom attachments, one of them being the scope. This means that the other attachment obviously isn't an unzoomed smart-link device, as the scope would already take care of that need. It's possible to be a flashlight, though this is unlikely because of how small the circular opening is, and the fact that the tip glows bright yellow in Halo: Reach.
So, to recap:
- M6D in Halo: CE - top attachment, zoom
- M6C in Halo 2 - NO attachments, NO zoom
- M6G in Halo 3 - top attachment, NO zoom
- M6G in Halo: Reach - top attachment, bottom attachment, zoom
- M6H in Halo 4 - top attachment, bottom attachment, zoom
- Not all M6 series feature a smart-link scope, per Waypoint, and Bungie's ODST and Halo 3 guides. Per our article on M6 series models which is appropriately sourced, the only known M6 magnums without smart-link are M6A, M6C, M6E, M6G, M6I, M6J and the M6K.
- The smart-link for the M6 series would be the top attachment. My guess is that the bottom attachment on the M6G/H (Reach and H4 respectively) would be some sort of laser sight/flashlight attachment, to assist the user in aiming (as if the smart-link is not enough if it's a laser sight attachment which I think it is!).
- I have my own theory as to why zooming doesn't work in Halo 3. Basically, since the M6G is one of the few dual-wieldable weapons in that game, it would break gameplay experience if the user can also zoom in while dual-wielding (either with another M6G or other weapons). Imagine a noob-combo with zooming! I guess Bungie wasn't able to fix this at all during development and came to an easy solution by removing zooming altogether (which would explain why they cut dual-wielding in ODST since fans want the zooming feature on the M6 magnum). But that's just my theory. :P — subtank 04:56, 28 September 2014 (EDT)