Rather than making Ironman-only versions of the boss chambers, could you do it for the god encampments? So when an Ironman opens the door for bandos, jumps the bridge at zammy, grapples the gap at Arma, or goes down the second rope at sara, they are put in the Ironman-only version. This means they'd be able to see who is in the boss room from outside rather than seeing a main inside and needing to peek and see if an ironman is inside like the current version seems to suggest. The peek option could still be there too, but it would be helpful to see the room the player would be entering.
As for the unnamed offhand, I picture it being bigger than a Defender (Parrying Dagger) so perhaps a shortsword like a Gladius? Anyway, I am still concerned about this one. There are two potential issues. The first is that it starts pretty strong with +15 for easy, which is hard to judge without knowing how early game it will end up being but it could be quite strong. The second is that Pures should be able to claim up to the Hard Tier, which is +25 and a massive leap over the Unholy Book; that is not in itself a bad thing but it is a pretty bit leap for something not clearly noted.
But my biggest concern with the offhand is that it might end up being OSRS's version of the Comp Cape problem. The Grandmaster Offhand is a niche item compared to the Avernic, but it still will have use for things like DWH specs, which are kind of a big deal. If it does end up being locked behind really hard achievements and players lose it over time as new content comes out, it would be the same as having to re-earn a Comp Cape and it could face the same pushback. Granted, this is more tied to combat than Comp, but it can still repeat much of the issue there of locking BiS behind Achievements that are often seen as prestige.
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