Halley’s Comet: A Calculated Prediction of the Star’s Return / Comet's Starlight: A Promised Performance, On a Grand Stage

In life, Halley could use various observations of small repeating patterns in the sky to determine how the Solar System functioned on a macroscopic scale. The most notable feat achieved from this was his calculations that accurately predicted the return of the comet that would eventually be named after him.    When calling upon this Noble Phantasm's True Name, Halley can accurately compute the future actions of anything through a one-time observation and be able to set up preparations for the next time the action is repeated.    As a downside, it offers no protection from any actions that Halley must see at least once to make the NP to be more effective.    When Hoshimachi is dominant, the True Name changes to "Comet's Starlight: A Promised Performance, On a Grand Stage." As Hoshimachi herself does not fully understand Halley's NP, the effects are reduced drastically.

Hoshimachi Suisei’s dream has always been to become an idol, to be recognized and loved by everyone around her. In life, she may have achieved this, but the current Heroic Spirit only has fragments of those times and memories.     Her wish for the grail is simple, she wants to be able to relive the experience of being an idol vtuber. Inspiring hope and happiness with the music she brings and to be able to sing again on the grand stage.    Edmond Halley on the other hand has already been an esteemed scholar in life recognized by many people.     So when being asked what his wish for the grail he simply replied:     "The Holy Grail? Why would I need such things?"     "For that comet to acheive her dream is enough for this old man."

Thanks to the connection Suisei had with her Vtuber self and Caster's Item Construction Skill, she can access a variety of weaponry related to her fame whenever she is in control. This can range from a gold axe, to Tetris blocks.    As for Halley, he uses the skill to create tools fitting for his calculations like compasses, pens, telescopes and any scientific equipment. 

"It's your shooting star, your diamond in the rough, idol VTuber Hoshimachi Suisei!"    Hoshimachi Suisei (星街すいせい) born on March 22 is a cheerful shining Idol and VTuber from Hololive 0th Generation. She is a forever 18, multitalented girl who deeply loves singing and idols, with the dream of one day holding a live concert in Tokyo Budokan. She started out as an independent VTuber and later joined Inonaka Music, a music label under Hololive, before moving officially to Hololive main branch.    Her name "Suisei" translates to "Comet" in English, and as such is usually referred to as the comet idol. She is well known for her amazing skills in Tetris, as she is often being called out as the best among VTubers, as well as her psychopathic personality, as shown when she sometimes acts ruthless to others while still giving off a cheerful attitude.    •••••••••••    Edmond Halley, born on Nov. 8, 1656, Haggerston, Shoreditch, near London, was an English astronomer and mathematician who was known to be the first to calculate the orbit of a comet later named after him. He is also noted for his contributions in the publication of Isaac Newton’s Philosophiae Naturalis Principia Mathematica. 

At the start of 2018 A.D., the Alien God's descent bleached the world and wiped out most of the Human Order.    Among its survivors is the girl who was supposed to have become "Hoshimachi Suisei". Despite the land becoming barren, despite losing everything, she still sang, alone in the middle of the bleached Earth, hoping that the world will come back to the way it was.    Perhaps because of her hopes for the future that a miracle occured.     Answering her calls was the Heroic Spirit, Edmond Halley, summoned by the Counter Force.     To save her life, the two made a contract, with Halley using the girl's body as the host, resulting in a Pseudo-Servant.    Because the Throne of Heroes was outside the Time, the girl eventually got the memories of her identity as Hoshimachi Suisei. However, she only has the memories of her Vtuber persona, so the only things she knows about Hoshimachi Suisei are the ones revealed to the public. 

I don't remember when I actually started making this project. Probably around Late August. (I only discovered Hololive on July)    Anyways, I made a Hoshimachi Suisei Servant because she's my favorite Hololive member and also, because the concept of vtubers is amazing!    I learned many things from making this fan Servant, particularly about Halley himself.     I would like to thanks to vz281#3703 and Ruka#3767 from Suisei's EN Discord for helping me in developing this idea. I couldn't have done it without them!