Help with understanding LP of CoF drops

Can someone help me understand what determines the LP of prophecy drops? Is it the level of corruption when I kill the required boss/enemy or the required corruption to complete the prophecy, e.g. killing a boss on corruption 140? Or a combination of both?

I’m trying to target farm both Culnivar and Tempest Maw and have gotten 20x LP1 Culnivars and 21x LP1 Tempests going from rank 5 to 9, avg 250C. I haven’t even counted the LP0s I’ve vendored. During this time, I gotten 4x LP2 Culnivars and 6x Tempests. I’m not sure if that’s the expected average or I’m just getting bad RNG. Or do I simply need to grind higher corruption?

Additionally, would it be possible to introduce the ability to shatter uniques (or a new rune that gives this ability) with LP to get a “shard/glyph of potential” to be able to augment LP on a unique? This would at least make duplicate uniques somewhat useful instead of 500 gold. Each tier would require progressively more shards/glyphs. I’m not sure how this would affect MG as I’m only playing CoF atm, but open to feedback.

As an example:

  • Shattering uniques with LP gives the corresponding amount of shards. Shattering a LP2 gives you 2 shards, while LP0 gives none.
  • Required shards to augment a unique:
    • LP0 - LP1 = 100 shards
    • LP1 - LP2 = 1000 shards
    • LP2 - LP3 = 5000 shards
    • LP3 - LP4 = 10000 shards