Cloak of Shadows (3.5e Invocation)
From D&D Wiki
While actively using the Hide and Move Silently skills, your profile blends in so perfectly with the terrain you're hiding in that you become temporarily impervious to all manner of heightened senses or detection effects, including spells such as true seeing and senses like Blindsight, Earth Sense, Lifesense, or Mindsight. Only a natural Spot or Listen check has any chance of detecting you.
If you perform any action that would normally bring you out of stealth, the effect ends until such time that you go into hiding once more.
In addition, you can hide in plain sight as a move action as long as there's a shadow or darkness nearby.