So after some reflection, and some digging, I think I have a tentative conclusion for the "all-purpose stealth character" that bypasses special senses. First, I made a list of special senses that can bypass hide/move silently I could find from checking around other similar lists on the forum:

Spoiler: Special Senses
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  • Arcane sight
  • Blindsense
  • Blindsight
  • Clearsight
  • Deathwatch
  • Detect (good/evil/magic/hostile intent/etc)
  • Discriminating Hearing
  • Dreamsight (pierces ethereal invisibility)
  • Dweomervision (Balhannoth, MM4)
  • Earth Sense/Other Tremorsense Copycats
  • Lifesense
  • Magic Jar
  • Metafaculty
  • Mindsight
  • Nemesis
  • Scent
  • Scent copycats
  • Sense magic (Mageripper Swarm, MM4)
  • Touchsight
  • Total Vision (Ethergaunt, Fiend Folio)
  • Tracking
  • Treasure Scent
  • Tremor sense
  • True seeing
  • Using Ice Assassin to gain your knowledge at the time of its creation



Then, I made a note of different ways we can foil those senses.

Spoiler: Senses w/ Some Corresponding Foils
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  • Arcane sight (use a mundane mithral tower shield for total cover)
  • Blindsense (Darkstalker; be incorporeal or ethereal; Cerebral Blind (Slayer 6))
  • Blindsight (Darkstalker; be incorporeal or ethereal; Slayer 6)
  • Clearsight (Slayer 6? Maybe God Blooded, as it's keyed off of True Sight? If it doesn't work, to be fair, it's only normally available to ECL 26 characters)
  • Deathwatch (Slayer 6)
  • Detect X (use a mundane mithral tower shield for total cover; God Blooded of Vecna; Slayer 6)
  • Discriminating Hearing (Slayer 6)
  • Dreamsight (Don't rely on ethereal invisibility/Slayer 6?)
  • Dweomervision (use a mundane mithral tower shield for total cover to block our magical gear)
  • Earth Sense/Other Tremorsense Copycats (Slayer 6; flight; be incorporeal/ethereal)
  • Lifesense (wear a bodysuit and have some other way to see OR be undead, probably with the Necropolitan template)
  • Magic Jar (Slayer 6)
  • Metafaculty (God Blooded of Vecna template erases all knowledge of you, so no one knows to use it; lose it and reapply it semi-frequently)
  • Mindsight (use a mundane mithral tower shield for total cover; Slayer 6)
  • Nemesis (Slayer 6)
  • Scent (Darkstalker; be incorporeal or ethereal; Slayer 6)
  • Scent copycats (Slayer 6)
  • Sense magic (No good answer; don't use magic items or spells. Use Duergars' psionic invisibility, or Malphas' supernatural invisibility)
  • Touchsight (be incorporeal or ethereal; Slayer 6)
  • Total Vision (No good answer; they will see our gear.)
  • Tracking (Be incorporeal/ethereal; flight)
  • Treasure Scent (don't carry copper, silver, gold, or platinum, or gems; a lead-lined tower shield should foil it)
  • Tremor sense (Darkstalker; be incorporeal or ethereal; Slayer 6)
  • True seeing (God Blooded of Vecna template; this also means we get an effective +20 to our hide for being invisible, providing we can be invisible)
  • Using Ice Assassin (God Blooded of Vecna template erases all knowledge of you, so no one knows to use it; lose it and reapply it semi-frequently)

    Senses with only one foil are in bold.

    Special note is given for Total Vision, which has no foil, and Sense Magic, which has no realistic foil. To be cautious, then, our best answer for these two are to just stay out of range (30 feet and 40 feet respectively).



As such, we more or less require Slayer 6, the God Blooded of Vecna template, either incorporealness/etherealness or flight, either to be undead or wear a full light-blocking body suit (and presumably have some sort of blindsight to compensate), and to carry a lead-lined tower shield (probably mithral to reduce the check penalty to our hide).

As Slayer can be entered at BAB +4, the soonest we're going to reach Cerebral Blind is level 10. I think lycanthropy could technically make us eligible earlier if we are humanoid, and could also help us hit the 4 ranks of Knowledge (dungeoneering) if it isn't a class skill. We also need a power point, either by race/template or by class.

We need to be able to cast second-level arcane spells to take God Blooded of Vecna. Precocious Apprentice could do this, or Versatile Spellcaster/Heighten Spell, or Versatile Spellcaster with the Dread Necromancer/Beguiler/Warmage.

We can get incorporealness (and therefore flight) for LA2 by adding the Telthor template, and trade out the negative features of the template with Dragonborn of Bahamut. This also blocks listen checks. Notably, this means we probably want a power point from a class or feat (i.e., Hidden Talent), as Dragonborn would remove our natural power point reserve.

We can avoid being undead by wearing a body suit and wearing a Blindfold of True Dark.

So, a Dragonborn Telthor Strongheart Halfling (LA2) could take their first level in an arcane casting class (wizard?), and take Hidden Talent and Precocious Apprentice as their level 1 feats. Then, they could apply the God Blooded of Vecna template to become an ECL4 character, trading out Apprentice for Track. They could contract lycanthropy (say, Brown Bear), gaining the animal HD. They take their second level in Slayer, then have the lycanthropy cured. As they level, they could train or Psychic Reformation away their prereq feats for things like Shield/Tower Shield Proficiency, or Ghostly Grasp (to save 10k on the Ghostwalk ring); they can also pick up the bodysuit, blindfold, and a mundane, mithral, lead-lined tower shield. That should cover everything by level 7, I think, so long as we keep a 40-foot distance from high-OP casters.

For a slightly less high-OP build (not abusing lycanthropy early-entry), we'd need a full-BAB progression class that grants at least arcane caster level 1. Duskblade should fit the bill, and has the Knowledge (dungeoneering) class skill to boot. We take Precocious Apprentice and Ghostly Grasp at 1, Wild Talent at 3, become Vecna-Blooded, retrain Apprentice into Track, and then go into Slayer, capping at level 10. It's probably more optimal to do something like Duskblade 1/psionic class 4/Slayer 6, though, to take advantage of the manifesting.