[Kameron8]

I believe that Spirit Pain should require a minimum of two enemies to trigger its effect, and that it should not function against Boss enemies.  

Using the invocation in a 1v1 scenario against someone who relies on basic attacks, or basic attacking mobs, provides a skewed reward for a D-rank invocation.  In many cases, it fully prevents any meaningful damage from being dealt for up to 7 rounds.  In a class that already has several strong tools against basic attackers, it stands out as something a little cheesy and uninteractable if it can't be silenced before it goes off. Items and gear can't mitigate the effect in any meaningful way, since it's a field effect that applies a status every turn instead of just being a one-time status.  

There is an argument to be made that nobody will use Spirit Pain once enemy count reaches 4 or more, and removing the effect against 1 target is a large percent of those use cases, but Hexer already has plenty of invocations that excel in high density scenarios.

[Autumn]

At minimum it should be adjusted to be not so all encompassing around 1v1s, but I believe the skill should likely just be reworked to be more friendly to use in any environment, 1v1 or teamfight or otherwise.

[zericosmic]

The only reason I don't use this in 1v1's is because it feels like cheating.