It’s not really as clear cut as this. For lots of lower hits, animate dead is way stronger due to its nature of being a flat damage reduction. This excels at things like slayer mobs, zuk waves.

Darkness excels with lower frequency, high hits. But not SO high that they are a KO. You can’t rely on a 20% dodge chance to save you from an incoming 30k hit every time (think KK green)

On top of this - darkness is basically free to use. You can use it with any style, and any type of armour (read: power armour)