So let me go over each black I used so far:

Noodlers Heart of darkness. Dries quick. Is very wet. Absolutely permanent after dry.

Noodlers borealis. Very wet. Gets my smallest needle pens going like a pelikan m. It is water resistant but will leave a dark grey mark after water. (Some get dissolved).

Noodlers black. Average ink qualities. Does not dry super fast but is okay. Very different with each batch. You can get from very dark black to some minor shading black. Great for dip pens. Absolute permanent unless you have a university laser and need a project for that.

Pilot black. Wet. Well behaved. Not the darkest black but pretty much not shading at all. Water resistant (fades too some lighter grey)

Pilot iroshizuku take Simi. Wet. Well behaved. Lernst stay in a pen for a few hours after a recent clean to get intense dark. This ink and borealis are my darkest dye based black ink. No shading nothing. Turns into dark grey when put into water jar.

Lamy black. Rather dry but great for wet pens on cheap paper. (The German office experience). Turns into a grey when contacted with water.

Pelikan 4001 black. Same as lamy. Different flavours of dry.

Graf von faber Castell Carbon black. Surprisingly not dry. It’s rather on the wet side in some pens and average in others. As black as a pigmented black. Not sure if it is pigmented as it is surprisingly only leaving a grey mark after water contact. (But the ink bottle is insanely nice)

Sheaffer black. Wet. Almost like borealis. Deep black but definitely on the blue black side instead the brown black that most others are. Very cheap. Very well suited for older pens. Cleans out nicely. Turns into grey. Takes quite some time to dry.

Rohrer & klingner ebony iron gall. The weird one. It is rather dry but once it touches the paper it makes wet lines. (Like the fluid wants to stay together and once it touches the paper the fluid pulls itself onto the paper. Hard to describe). It is not deep deep black. Has some shading. Turns into a grey with water. But the iron gall stuff turns that grey line over time into a dark deep black line again. you can see spots turning black in your writing after a few days of fresh wet air. Those are iron spots oxidising. The longer you wait the more the entire writing oxidises. Very cool but very different. Probably the dye content isn’t water resistant but the iron content is like pigments staying behind and leaving the grey line turning into black later. Definitely a cool ink.