This is really well done! These are solid and very powerful magic items with nice flavor. I could see a fun campaign-wide quest to gather all four antiquities to defeat some fallen celestial trying to undo the laws of time.
I'm not super well studied on the divine lore of Orden, so I honestly found the first section pretty hard to follow. That isn't necessarily a bad thing if you're intending for it to be a more cryptic passage that rewards those with greater setting knowledge. But just thought it was worth noting as someone that has skimmed the mythos but isn't in very deep, it was a bit confusing.
Another minor note, I think the Floebreakers would have the "unarmed" keyword. If they're meant to be weapons (which the ability text describes them as) they would need that tag to fit into certain kits. You might also want to add the "head" keyword to the masque of the reaping, unless it isn't meant to be worn? If not, it might be worth describing as a totem or something.
Not a factor in the jam rating, but I also really like the layout on this! The background and borders are a nice touch that make the end product look more put together. Good typeface choices too, I think we use the same header font in our projects haha.