Staedtler makes the best 8B pencil.  It is soft and you can achieve very black blacks. If you don't buy the whole set at least invest in the 8B.

Staedtler Mars Lumograph Graphite Wooden Pencils ~ I have this same set- it was my first set of graphite pencils.

All-black pencils

Black Dyed Pencils Don’t just show up to class, show up to class with these black dyed pencils that will strike fear into the hearts of exams, essays, and pop quizzes that dare stand in your way.

pencil talk | pencil reviews and discussion

Les crayons de la maison Caran d’Ache, Edition No. 2 That blue zebra!

Kita-Boshi Vermilion and Prussian Blue 9667 pencils

Red and Blue pencils VI – the Kita-Boshi Vermilion and Prussian Blue 9667 pencil – pencil talk