Eternity

Eternity is a craftable post-Moon Lord developer spell tome. When used, it will create a large circle, which inside will have five crystals, a beam, and a group of projectiles that create a flower shape while traveling, all of which will be centered around a nearby enemy. The beam will travel in an infinity shape. The crystals will circle the targeted enemy. The flower-shaped projectiles will also harm nearby enemies. If the attack button is held, the beam's path will slowly grow in size as the beam changes to a darker blue color. Eventually, if the attack is held for long enough, the beam will disappear and the crystal circle will collapse in on the target, causing massive flower-shaped explosions that inflict massive damage.

Trivia

 * The weapon's Beam projectile path follows the mathematical sign Infinity (∞), which fits with the weapon's 'Endless' theme.
 * The infinity sign (among other 8 and ∞ shaped curves) is a shape called a Lemniscate.
 * The tooltip on how the book has pictures of ponies in it is a reference to My Little Pony: Friendship Is Magic, a show the dedicatee is a fan of.
 * This, along with Apotheosis and Elemental Excalibur, are the only weapons crafted from Shadowspec Bars that do not drop from Supreme Calamitas.
 * This weapon actually has a unique rarity, but is referred to here as Hot Pink for consistency between weapons.
 * This unique rarity alternates between grey (#bcc0c1), purple (#9d64b7), orange (#f9a64d), pink (#ff69ea), sky blue (#43ccdb), yellow (#f9f563), and pale purple (#eca8f7).
 * These colors are references to the main cast of My Little Pony: Friendship Is Magic: Rarity, Twilight Sparkle, Applejack, Pinkie Pie, Rainbow Dash, Fluttershy, and Starlight Glimmer, respectively.