|Well, congrats. You discovered it. You get to name it.|
Although this article is based on canonical information, the actual name of this subject is conjectural.
The Fear Manifestation Ritual is a ritual that brings a person's fears to life and are used to kill that person or another person.
Wanting to help children, rejected for a manager's position at Plucky Pennywhistle's Magical Menagerie and emotionally traumatized by the death of his brother as a child, Howard decided to use the ritual to kill bad parents as he believed that they needed to put their children first. Howard set the ritual up in the subbasement of the store and used it to kill a man who was hitting on the babysitter, a bad father and Saul who was planning to reveal what he knew about Howard's actions, manifesting a vampiric octopus, a unicorn and a shark for the three.
After Sam Winchester started investigating his actions, Howard set two clowns after him to kill him, but was confronted by Sam's brother Dean who turned the ritual on Howard, using his own fear of his brother's drowning to summon the ghost of his brother who drowned him. Howard's death broke the spell he had cast to kill Sam and the clowns disappeared.
While investigating the subbasement of the Plucky Pennywhistle's Magical Menagerie store, Dean found a bowl containing a fire set up in the middle of a sigil that was used to cast the spell along with a spellbook describing how to perform the ritual. When confronted, Howard explained that the ritual feeds off a person's fear which leaves a bit of fear magic behind when it is drawn. To activate the ritual once it is set up, a person must simply toss a drawing of the fear they wish to use and an object belonging to the person they wish to target into the fire. Howard used this method to kill three people and try to kill Sam, but Dean was able to turn the effects of the ritual on Howard himself by tossing in a drawing of his brother drowning (his greatest fear was water and his brother coming back for revenge) and a ceramic doll he'd made of a clown, summoning the ghost of Howard's brother who appeared as a vengeful spirit.
When Howard's brother drowned Howard, the clown creations he'd made with the ritual to kill Sam disappeared, indicating that the power of the ritual is tied to the caster.