Dr. Awkward said:
That's a problem with the DM, not the warlock.
As we have already established that one single least invocation isn't this pony's one trick, it isn't a problem at all. Why should all of its powers be neutral? Take a look at the Dragonfire Adept (which is very similar to the Warlock). He has two big fat super invocations - but one's for good guys only, the other for the bad guys. Noone's crying havoc about that.
In fact, even if that one invocation made you lose 2d12 sanity points or slapped several ranks of Shadowlands Taint on you, it wouldn't suddenly make the whole class unplayable for good characters or anything.
Which fits in with the "I got my powers from evil, but I'm not evil...I'm so tortured and misunderstood" flavour of the warlock. It's not a flavour I like too much--I got enough of that shtick from V:TM back in the day.
The Warlock isn't nearly as drama queenish as Vampire is always said to be. It's no different from a non-evil necromancer. Dark doesn't mean Evil. But if that necromancer indeed creates and employs undead, he's on the best way to become evil.
The flavour was always optional.
Not for me it isn't. This isn't Diablo. You don't just use things to kill more monsters and find that Unique Elite Item or the last piece of your set. You either work with the flavour, or you make your own. You don't just ignore it.
Besides, why can't a good guy use the tools of evil against it? Irony, etc. "Evil has, in me, created its own greatest enemy! Bwa ha ha!"
Because, counter to what some people believe, the end doesn't justify the means. "If you stare too long into the abyss..." "sheep and shepherd..." and all that.
If you use [Evil] stuff, you walk a path that will lead, sooner or later, to Evil.
You can get a way with it once, maybe a couple of time, but sooner or later, it shows on your record.
Dr. Awkward said:
The designer said it's meaningless flavour text.
Where does he say that?
If he does, then the first reference must be corrected to:
"That's a problem with the designer, not the DM or the Warlock."
To make this not be something that puts you on the Path Straight to the Dark Place, the text would have to be changed, and possibly the name.