Arachna

Arachna is a powerful spiderlike deity of Creation and Order who, in the SW continuity, is responsible for the existance of the primary Earth and Gensokyo. She is also the mother of Arachnos.

Hellgate Saga
Though often mentioned, Arachna only personally appeared once in the Hellgate Saga, to fight Hellgate in Hellgate 2 Part 1 after SDM (his roleplayer) allegedly "lost control" of him. Most of her interactions with Hellgate consisted of him claiming that she's no better than him, and her trying to refute that. She was responsible for freeing Patchouli Knowledge from Hellgate's influence, but only thanks to a tip given to her by an as of yet unknown source.

Hellgate 2 Part 2 What If
Arachna appears in this hypothetical scenario, which depicts what would have happened if SDM had gotten re-infected by a Dark Spore during the Black Spawn invasion on Gensokyo. Due to her personal hatred for Hellgate, she first imbues Arachnos with her power and then subsequently engages the infected house through an avatar, to no avail. When Hellgate kills Arachnos and reanimates him under his command, Arachna finally deigns to interfere personally. But Hellgate promptly becomes so sick of her that he unleashes an attack with his full fury, which pierces through her defenses and mortally wounds her, dooming both her and her soulbound rival god Enthropod to die and taking her out of the battle.

Her final action is to grant a divine empowering to the protagonists using the last of her strength (which actually did allow the group to defeat Hellgate, thus marking a rare occasion when Arachna actually did anything useful), before expiring shortly after.

Xat RP
Arachna is at her most active and most incompetent in this roleplay, though it does not immediately become apparent. She uncharacteristically made an alliance with Hellgate (who all but ruled Equestria at that point) so as to avoid plunging the world into chaos, especially when a greater threat in the form of the Red Brother presented itself. When Anathemus awakened, she helped relocate most of the Equestrians to another universe to keep them safe from his wrath, and was also among the ones who fought Hellgate when he went rogue after his plans crumbled. She witnessed and barely escaped the subsequent arrival of Anathemus, and this is where she starts to fail at everything she does.

She arrived to the second Equestria and, in a panic, cried wolf about Hellgate's power to summon Anathemus (a power he no longer had at that point). Her insistence caused the inhabitants to let Hellgate rampage unopposed, letting Equestria be destroyed in vain and allowing Hellgate access to Techquestria, where Arachna's error was finally revealed. The goddess immediately went berserk and tried to kill Hellgate, but failed to accomplish even that.

She would proceed to be mostly unimportant until the introduction of the Fourth Equestria. There, Arachna (seeming to have no memory at all of the previous events for yet unknown reasons) did not recognize Orachnos and Tarachnos as her own spawns and tried to kill the group of Anathemites, a fate from which they narrowly escaped. As they developed their Nihility powers, word of that reached Arachna, and she once again tried to kill them out of misplaced pride. Naturally, she underestimated them and was beaten to near-death by the masters of Nihility. This caused her to flee the world out of fear and humiliation, disowning that universe completely and leaving the local Arachnos depowered.

Appearance
Arachna usually appears in the form of a fantastically large black widow spider with a red circle where the hourglass would normally be. She has also been known to take the shape of a black-haired woman wearing tight leather clothing.

Personality
Although she is not evil, Arachna is a good example of a "jerkass god". She has the flawed perception that because she is a goddess, she can make no wrong decisions - even though she is not actually entirely omniscient and has been known to make rash and idiotic decisions out of fear, pride or rage. She believes firmly believes in might makes right... as long as the might is on her side, naturally, otherwise she starts screaming injustice.

Arachna is incredibly arrogant, and cannot stand anyone who questions her decisions and authority - unfortunately for her, this actually includes a lot of people, such as SDM, Hellgate, and sometimes even her own spawn Arachnos. She speaks in an incredibly dramatic and over-the-top way and just about every single sentence she usually says consists of praising her own greatness and omnipotence.

Despite her incredible power, Arachna usually cannot be bothered to intervene in conflicts that could have been easily resolved by her, even when the fate of one of her worlds is at stake. She will only intervene personally against enemies that damage her personal pride - usually by attempting to become deities themelves, such as Hellgate.

Arachna is a goddess of Order and detests any and all forms of chaos, though usually she doesn't go any further in battling them than sending out her envoy, Arachnos.

Powers and abilities
Arachna is a creator deity with enough power to make entire universes, the fabric of which she "weaves", fitting into her spidery appearance. Because she has full knowledge and control over her own "webs", Arachna is essentially omnipotent in a universe of her own creation.

In dimensions created by other deities, she is slightly less powerful. She can still create her own constructs, however she cannot use her divine power to undo or affect the creations of other gods. Her effectively infinite levels of energy and powerful magic still make her a formidable opponent.

In normal circumstances, Arachna is immortal. Even if she were to be destroyed, she would promptly regenerate back to life. Exceptions exist, though (see below).

Flaws and weaknesses
Arachna is not invincible. Deities of similarly immense power can clash with her and match, or sometimes even outmatch her, however almost none have the power to destroy her for good.

In addition, her power absolutely pales before that of Anathemus, to the point that a few Anathemites can easily tear her apart even in one of her own universes. In a What If scenario, Hellgate was also able to mortally wound her using an all-out attack fueled by his God Aura and his own overwhelming rage. Because of its nature as the complete cessation of existance, Nihility is one of the very rare forces that can actually kill Arachna for good and forever.

Relationships
Arachnos: spawn and personal enforcer. One Arachnos exists on every world of Arachna's creation to uphold order. Arachni can occasionlly also mate with Arachna, but the details of this are best left unrevealed.

Black Brood: Spawns and personal army. Deployed on a world as support for Arachnos.

Enthropod: God of Chaos and Arachna's greatest enemy and rival. Even though they would love to, the two cannot actually kill each other, as the death of one results in the death of the other.

Anathemus: A god able to effortlessly crush her, Anathemus is Arachna's greatest fear. She will avoid any conversation about him whenever possible. At the same time, she has been known to underestimate things related to him, such as Hellgate and Anathemites, believing that a mere fragment of Anathemus' power would not on its own be enough to overwhelm her. She is usually wrong.

Black Spawn: Arachna fears the Black Spawn, because a Dark Spore could potentially infect even her and turn her crazy.

Hellgate: Arachna has a personal hatred for Hellgate, due to his goals of attaining godhood and his utter disdain for her.

Trivia

 * Arachna was originally primarily intended as a counter to cheap characters (her noninterferal policy is intended to hold her back from solving any problem on her own effortlessly), but eventually ended up playing a larger role in the lore and even intervening in some events.
 * Arachna can be seen as a deconstruction of the "single, omniscient and omnipotent, benevolent deity" found in most monotheistic religions.
 * Arachna can be considered as the foil to SDM (player)'s ideals, perfectly representing everything he detests about gods. This makes her a frequent target for well-deserved ridicule and abuse in the Mythos, especially in the Xat side-RP. Almost every attempt by Arachna to interfere in anything ends with her making things worse than they were before.
 * Ironically, the incident that firmly cemented Arachna's reputation as an inept deity (her false warning to the Second Equestria) was due to her roleplayer's own misunderstanding - at the time, Arachnos thought she was right.