Trapfinding and Magic Traps
Magic traps such as Phineus' writhing tentacles are hard to detect and disable. A character with the trapfinding class feature (only) can use the Perception skill to find a Phineus' writhing tentacles and Disable Device to thwart it. The DC in each case is 25 + spell level, or 29 for Phineus' writhing tentalces.
Whenever anyone but the caster touches or opens the protected book, writhing gray tentacles emerge from the ground in a 5 ft. radius centered on the book. The spell creates 1d4 tentacles, plus an additional tentacle per caster level up to a maximum of fifteen tentacles. For example, an 8th level wizard creates 1d4+8 tentacles. Each tentacle is 20 feet long (Huge) and has the same saves as the caster at the time of casting. It has an AC 16, 1 hit point/per caster level and an attack bonus of +1/per caster level. The tentacles also have construct traits. The tentacles attack as mindless creatures, randomly striking anything, including anything larger than a tiny object. On a successful hit, the tentacles deliver 1d4 points of damage, and also secrete thin, black mucous through their porous skin. Any creature struck by one of the tentacles must make a successful Reflex save DC16 or be blinded by the foul liquid for 1d6 rounds. The tentacles are immobile, and once summoned remain in existence for 1 round/per caster level or until slain, whichever occurs first.