Which spells did the Half-Blood Prince invent?

Answer 1

I'll name one; people can discuss if they want:

Sectumsempra; invented by, non-the-less, Severus Snape.

Answer 2

Severus Snape, aka the Half-Blood Prince, invented a few spells:

• Langlock - a jinx that causes a persons tongue to stick to the roof of their mouth.
• Levicorpus - a jinx that hoists the victim in the air by their ankles.
• Liberacorpus - the counter curse to levicorpus.
• Muffilato - a charm that creates a buzzing noise in the ears of people around the caster.
• Sectumsempra - a curse which creates deep slashes on the victim.
• A toenail-growth hex.

Answer 3

Harry finds a number of spells that the Prince invented himself, such as:

Levicorpus - a jinx that causes a victim to be hoisted into the air and dangle upside-down. It is better performed nonverbally.

Muffliato - a charm that fills a surrounding area with an unidentifiable buzzing, so to provide a private environment for a conversation in a public place.

Sectumsempra - a Dark curse - the equivalent of an invisible sword, slashing the target repeatedly.

Answer 4

Sectumsempra, Levicorpus, Liberacorpus, Muffliato, Langlock

Answer 5

Sectumsempra.

Answer 6

Sectumsempra