[X] My Assistant

(note: This investigation is a precursor to something else, but I don't know if I will ever get around to writing about it.)

Although there are still things to investigate above, here's Part 2 of this discussion. I don't know if anyone mentioned this before but TL;DR Banshee weapons are good in the Tower because they will suck out the Spirit of the enemy being targeted. That pesky enemy that you couldn't stick Weaken/Silence on won't be able to use its Spirit attack on you. After more tests, Banshee weapons seem to work as follows:

• Siphon Spirit proc chance works as stated, is not affected by critical hits, and goes up to 30% on a Peerless weapon
• Siphon Spirit proc effect is 0.87% base drain on my Magnificent Rapier, this scales up with player level and equipment quality, like proc duration
• Siphon Spirit proc effect amount does NOT work as stated, in an obvious way
• On my Magnificent Rapier, the log states the amount drained each time is 1~6 SP. It drains as a fixed ratio of what the target monster's currently filled SP is.
• The drain SP written in the log is correct for what is added to your own Spirit bar. Occasionally it's off by 1 SP, so I think actual SP is fractional and rounded in the log.
• I get 1 SP (display log) if the monster has zero SP, all the way to if the monster has a decent amount. I only get 6 SP (display log) if the monster SP is perfectly full.
• The monster loses 2% of its max SP times the number of SP you got. If the log says 6 SP, then the monster loses 12% of its max SP.
• All target monsters seem to be affected the same, regardless of their stats, level, or PL, and including even schoolgirls and Flying Spaghetti Monster.
• Difficulty does not affect any of these Spirit Siphoning amounts
• The amount of damage you do, or activating your own spirit stance, do not affect these Spirit Siphoning amounts
• On IWBTH, siphoning 2 SP is enough to keep a monster's SP bar unchanged that turn. Because it's fractional (?) sometimes 2 SP will let the monster fill slightly.
• On PFUDOR, siphoning 3 SP is enough to keep a monster's SP bar unchanged that turn. Because it's fractional (?) sometimes 3 SP will let the monster fill slightly.
• If your siphon attack is a deathblow, the dead monster will have lost more SP than usual, this is because it won't regenerate its own SP on that turn

I will not say my tests and these results are complete, rigorous, or precisely correct, but perhaps they could be correct to see how it works. I am switching to an Illithid Rapier now. I suspect it will work the same, but because monster MP fills twice as fast and needs half as much to activate (and together with the drain being proportionately less when the monster bar is less full) I think it will not be enough to freeze monsters like Banshee. Even if a monster has already filled its SP bar, all you need is one lucky Banshee strike and you will buy yourself at least two whole turns of no monster Spirit attack.

Just confirming my observations regarding my Illithid weapon before I forget and retire from the season.

• Siphon Magic prof effect is 0.93% base drain on my Legendary Rapier, this scales up with player level and equipment quality
• On my Legendary Rapier, the log states the amount drained each time is 1~8 MP. It drains as a fixed ratio of what the target monster's currently filled MP is.
• My isekai character has about 1530 MP and 1170 SP at around level 350.
• I theorize that the upper maximum of the HP/MP/SP drained could be the stated ~1% percentage times your character's base HP/MP/SP.
• On PFUDOR, even siphoning 8 MP will not reduce a monster's MP bar, it still wants to fill slightly.
• On IWBTH, siphoning 8 MP will reduce a monster's completely filled MP bar just a little.

The performance with MP drain was even slightly worse than the previously hypothesized poor result, for unknown reasons. I probably don't have the general method to calculate the monster HP/MP/SP loss exactly right. We know that they lose an order of magnitude, roughly ten times more than we'd expect. It's amazingly helpful on Banshee weapons to silence monsters, but not enough on Illithid weapons even though it works the same. Vampire weapons might be less laughable than people realize, if the HP drain to monsters is major. This would be difficult to test because we can't see the amount of HP sucked out of monsters' health bars, and we can't trust the log as it only states the HP that we gain.

It's also possible that your other stats might somehow affect the HP/MP/SP loss to monsters. What if proficiencies, Demonic weapons, or your Intelligence and Wisdom stats, increase the damage of Vampire weapons? (similar to the Drain spell)