Pennywise turns into a giant spider because that's the closest form its ancient, cosmic true self (the Deadlights) can manifest that human minds can comprehend as a terrifying, tangible creature, especially when facing its ultimate defeat in the sewers. While Pennywise the Clown is its favorite disguise to lure victims (especially children), the spider form represents a more primal, monstrous reality that the Losers' Club confronts when they challenge IT's physical presence in the novel.
The adult Losers finally reach Pennywise's lair and find It has taken the form of a giant spider.
Pennywise (It) is deeply connected to The Dark Tower's lore as an ancient, cosmic being from the Macroverse (or Prim), a dimension outside normal reality, making It part of the same supernatural ecosystem as Dark Tower entities like the Crimson King and the Turtle (Maturin). Both It and the Crimson King are chaotic forces seeking to unravel reality, with It feeding on fear and acting as a powerful, ancient predator that briefly inhabits Earth, serving the larger cosmic struggle for the Tower itself.
Pennywise sleeps for about 27 years because it's an extra-dimensional being whose hibernation is a natural, cyclical part of its life cycle to regain energy after a feeding frenzy, allowing it to feed on the fears of children in Derry every few decades, with the number also serving as a literary device for generational trauma and cyclical horror, making its return predictable yet mysterious.
It is the only live-action villain role of Tim Curry to be Pure Evil so far. Its 1990 incarnation was the first Pure Evil portrayed by Tim Curry, giving him (Alongside Robin Atkin Downes) the second highest acting and voice acting amount of Pure Evil villains after Jim Cummings.
It (also commonly known as Pennywise) is an ancient alien/eldritch monster and the title character and main antagonist of Stephen King's best selling and award winning 1986 novel of the same name and two duology film adaptations (IT (film) and IT: Chapter Two).
Pennywise/deadlights can easily eats valak's soul since Valak is a demon but the deadlights is an cosmic entity outside of our universe.. To put it simply, Pennywise is a multiverse threat. And a mere ghost or demon like Valak stand no chance against IT. Pennywise can eat souls and manipulate reality.
When "It" is about to eat Beverly, she displays fearlessness to which Pennywise said it was ok and that he knew what would make her scared. He then proceeds to open his mouth hella wide and reveals 3 small lights inside of him. This somehow scares her enough that she falls victim into the floating trance.
Instances of that number may be indicators that the Keystone World is involved and that the ka-tet should pay special attention to it. It is well known that Stephen King started writing his Dark Tower series at the age of 19. It may be this that led him to the idea of choosing 19 to be of such importance in the books.
Essentially, the Deadlights are a universal representation of cosmic evil that powerful entities, like IT and the Crimson King, can access or embody.
IT represents chaos, evil, and fear, while the turtle is a force of kindness led by compassion, making them direct opposites. Both being interdimensional entities, their powers are at the same level, meaning that the turtle could kill IT if it wanted to.
Upon looking at the Deadlights, Beverly hears sounds of children screaming, including an older person who shouted "HELP ME!!!". This implied that the Deadlights, and, to an extension, It, did not just eat their flesh and fear, but their souls as well.
It was seemingly able to reproduce by itself when it laid eggs at the end of it chapter two. But since it can also give birth like humans do. It either uses reality warping powers to make it so pregnant or it actually managed to seduce a poor soul into falling in love with it.
Pennywise (It) goes into a deep hibernation beneath Derry, Maine Fandom, often in its subterranean lair in the sewers, after being forced back by the Losers' Club, using the ~27 years to mature, rest, and regain strength before awakening for its next cycle of terror. This ancient, trans-dimensional entity feeds on fear and emerges roughly every 27 years to cause mass destruction in Derry, its chosen feeding ground, before retreating again.
It: Welcome to Derry, episode 1's shock twist ending saw the majority of the new gang of kids, set up to be the new Losers Club, murdered and devoured by Pennywise's murderous demon baby form.
As well as having his right arm bitten clean off, Georgie is trying to crawl away but he was dragged into the sewers and devoured by Pennywise, with an unnamed older woman and her cat being the sole witnesses of the horrific scene, including before Georgie lost his arm.
Pennywise's main weaknesses are courage, unity, and the power of belief, which directly counteracts its reliance on fear, making it vulnerable when victims stand up to it, unite, or assert that it's not invincible. Its physical forms, chosen from victims' imaginations, are bound by the rules of those forms (like silver for a werewolf), and it's also limited by its 27-year hibernation cycle and the magical barriers of its meteorite origin.
The tall man is also an interdimensional being who can manipulate time, space, and death to his liking. He would easily be able fight back against Pennywise's illusions which essentially would make Pennywise weaker. I think the obvious next pick for this would be Pinhead.
Valac is a demon described in the goetic grimoires The Lesser Key of Solomon (in some versions as Ualac or Valak and in Thomas Rudd's variant as Valu), Johann Weyer's Pseudomonarchia Daemonum (as Volac), the Liber Officiorum Spirituum (as Coolor or Doolas), and in the Munich Manual of Demonic Magic (as Volach) as an ...
It's primary goal is to feed on humans, generally preferring children over adults since they were easier to scare and manipulate. According to the creature, frightened flesh tastes better and uses fear to "salt the meat".
Pennywise is an ancient, evil being that originated from the Macroverse and has a specific corner of the cosmic realm called the Deadlights. Pennywise takes the form of whatever its victims fear the most, but its true form has been described as an endless, crawling, hairy creature made of orange light.