Provide a detailed and clear description of feature or change that you want to offer.
The ancestor inscrutable eye is pretty cool. But I keep having this idea that might be rather interesting. Basically a modpack maker could repurpose it with their own sound files and make the eye react to different advancement like triggers. Either repeating periodically (on a cooldown, or every time it triggers like the death lines) or once (after a first kill of a boss/entrance to a dimension etc).

Basically you'd use a slightly different form of advancement that doesn't pop up a toast, which also takes a voice file sound to be played and possibly either a direct or localized transcript/on screen message displayed in text while the sound plays to create custom voice over/narrator kinda thing using it.

Describe why you want this. If there's a reason.
Just an idea that could be cool/useful for pack development. I remember vazkii had something of the sort way back but it was a bit of a throw-away idea as it never got updated past 1.10... "vocation" I believe. although that could also run commands and such whenever it triggered lines+words... I dunno, bonus points if you want the entity to send presents? :V