[Snake]

Easy deal, but takes a wee bit of work to make, probably.

At the battle start, Parasitic grants one Buff and one Debuff.

"Symbiosis" buff starts at LV(10% of your maximum FP at combat start).
- Grants bonus damage to all actions by 5+(LV*0.5)%, (max. 25%).
- If your current FP amount falls under 2.5x of Symbiosis LV, Symbiosis is removed.
- Permanent duration, cannot be cleansed or stolen.

"Parasitism" debuff starts at LV0.
- Reduces all healing and FP recovery by 75%.
- Every time an offensive action is done, its LV increases by Symbiosis' LV in an additive way; this lowers maximum FP while doing HP darkness damage that ignores protection, both equal to Parasitism LV.
- Permanent duration, cannot be cleansed or removed.

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The genius of it is, with Symbiosis removed, the LV cannot be increased anymore so once the 'best' of the weapon is used, you're left with 20% of your max FP, 75% HP reduction and no damage bonuses. And since Symbiosis won't exist, the LV for 'leeching HP' will be 0, therefore it will also stop mooching from your HP.

Yeah, 'boo', not as lethal as the OG but this makes a bit more sense. If every cursed weapon has the potential of killing you, merchants would be damn rich by now for selling those and retrieving from the corpses, lmao. ANYWAY moving on!

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I think Haunted Soul is already underwhelming, and I can't think of any better gimmicks that fit its theme. Maybe within every basic hit you slowly reduce both of yours and the enemys' status resistance with no cap? We don't really have a real counter to that yet. I can think of it reducing 5% of your Status Resistance and the enemy's, permanently, over time. If you attack them while they are feared.

Modifying from their 'natural -25% Stat Res' drawback:

Haunted Soul - Attacking Feared enemies inflicts a debuff, on yourself and your target, that reduces Status Resistance by LV for 5/10/Inf rounds. (Max. 90%)