Does Touch of Cruelty stack?

I am pretty sure it does but I just want to double check.

10% chance to cause Hinder and enemies take 10% increased chaos damage.

I know Hinder doesn't stack but with two Touch of Cruelty, it should be 20% increased chaos damage taken?

cluster jewel notable are stackable

Thanks for the answer. You seem to know a lot. I have a side question.

I am planning a Soulrend build and I see that there is Septic Spell that makes Spell do poison damage. Since I am already stacking chaos damage, does Poison Spell improve my damage a lot?

I know Unnerve debuff only improves Hit damage.

Enemies take Increased Chaos Damage apply to Damage Over Time right?

1. Two Touch of Cruelty give you
Chaos Spells have 20% chance to Hinder Enemies on Hit
Enemies Hindered by you take 20% increased Chaos Damage

2. All small passive skills and notables (except for few specific modifiers with global cap) are stackable. To stack something though, you must have at least two things, and since any fixed and non-conquered notable is one of a kind, you can't stack it in practice. In contrast, Keystones are not stackable. Meaning that even having multiple of them allocated (timeless jewels allow that), only one would work.

3. Poison inflicted by Soulrend is scaled by the same modifiers (plus poison related of course), excluding spell damage. It seems interesting, but poison is not popular in chaos DoT spell builds. For numbers you should use PoB. To rely on poison you wanna have 100% chance to posion, also you probably should prefer DoT focused supports, e.g. Cruelty or Efficacy over Empower or Controlled Destruction if you have to choose.

4. Right. Soulrend's hit deals chaos spell damage, while Soulrend's debuff deals chaos damage over time. Unnerve increases spell damage taken and only Soulrend's hit deals spell damage. "Enemies take Increased Chaos Damage" will increase damage taken by Soulrend's hit and DoT since both deal chaos damage.

Thanks!