Favorite blackest black ink?

I own a rainbow of beautiful colors, mostly from Diamine, but what I really miss a a truly black ink for formal days. I have a big bottle of Parker Quink Black, but I almost never use it as it's actually a middle-to-dark-gray ink even with my flowiest pens.

So what are your favorite, deeply saturated black inks?

Bonus points if it's (very) affordable and easily available in Europe (so no noodlers).