Dead NPCs refuse chats if youve killed them personally, but casting disguise self beforehand solves that issue right away. The amulet of lost voices from the dank crypt lets anyone use this ability, not just spellcasters, which is pretty handy to keep in mind. Speaking with corpses wont bring them back to life obviously, but the info you get can seriously change how certain quests play out

Good to remember that undead bodies, anything too burnt up, or acid-damaged corpses wont work with this spell, and youve got a limit of five questions per body before the magic fades. No need to worry about reputation hits or alignment problems, its totally fine to use necromancy this way. Just make sure to grab that amulet early on, and definitely keep some disguise self scrolls handy, since a lot of corpses might recognize you as their killer otherwise

Remember that this can unlock some really interesting quest paths and treasure locations, especially in spots like the open hand temple investigation, so its worth using whenever you find fresh bodies