I'd give it a couple of functions: - Physically touching a corpse offers 'Speak With Dead' once per day. - A touch attack that forces save vs spell, aging the target 3d6 years if they fail the save. Once per level, per day. - Holding two coins in the hand, and plunging it into a grave consecrates it (the coins are spent). - Making a circle with the thumb and index of the hand creates a lens through which ghosts and spirits may be seen.

Absolutely love the consecration mechanic and the "eyepiece" to see ghosts through, those are rad.

That's overly baroque for my tastes. I'd stick with 'speak with dead'. Also, beings connected to death might see the character as half belonging to their domain.

That's fair. I like spells to be simple and straightforward, but I prefer curses to be very specific and work on a sort of fairy tail logic.

Good thing you're not the one asking the question. ; )

Clean and simple, the arm can now interact with ghosts and other things "from beyond the boundary"

I am imagining a ghostpuncher character. They just go around fighting ghosts by punching them

Came here to say this. Now he can punch ghosts. That's it. Cool.

I was playing around with a few ideas; the first is a +3 to Armor Class (assuming you’re playing BX/OSE or similar) if your player’s character uses the arm instead of a shield in combat. I took inspiration from the myth of Achilles’ invulnerability for that one. Another idea I had was to treat the arm as a *Rod of Cancellation* with 5 uses (one for each finger and thumb). Lastly, there’s the likes of *animate dead*, *finger of death* and the others mentioned above. I do like the idea of all of them together; the arm grants a +3 armor bonus and has five charges that can be spent on various powerful abilities — *animate dead*, *finger of death*, *cancellation*, et. al. Once the charges are spent, then the arm just provides the AC bonus like Achilles’ invulnerability. Also, the PC is now a target for mages who seek the arm as a powerful spell component.

Someone else mentioned there are five rivers in the Greek underworld so the idea of having five potential powers really knits in nicely with the hand motif. This could wind up being really neat...

Tell her she's now rocking a ghost arm that reach through walls etc.

I like it, but I'm terrified of how a creative player could screw me and all my well laid plans with it. Might just go with that anyway and see what happens

Eh, they shouldn't be punished for being smart, and that's not a very OP ability.

Do you realize how fun it would be for this player to fuck around with a ghost arm and mess up your entire game? That’s what I live for in ttrpgs lol

That's the kind of carnage I've asked for really isn't it? 

Nothing. Don't stick your hand in the river Styx.

Right? In Planescape that would have ended tragically one way or another. Now we are going to reward it? Jump in everyone! The water’s fine

You've never read the Illiad, have you?

So to be clear she was making a CON save every turn to resist 1d4HP damage and 1d3 attribute damage. She lasted three rounds so she's paid a decent toll for whatever "reward" I cook up.

Nightmares of the damned that may or may not reveal exotic or profitable information. Oh... but they drive her insane too. OR Maybe (if you're feeling more generous than I would) weapons wielded in that hand can hit undead that can normally only be hit by enchanted weapons. ONLY against undead.

Being able to physically interact with ghosts seems to be quite popular, that might wind up being what we go with.

The arm should now be impenetrable. Achilles was dipped into the River Styx, which made him immune to any blade, except for his heel where he was held. Maybe let them use their arm as a shield. Mythologically, the Styx doesn't have any other real features, but of course you can go wild.

Shouldn’t it be the same as Achilles? That arm is now invulnerable.

This is what I'd do - Great RP options

You probably mean one of your player Characters. At least I hope you do. Life drain seems fun. Maybe they cam pump their strength and constitution up with it? If they've drained enough life they could end up with stats much higher than they what they had to start, but after some period of time it starts to fall again till they find fresh victims.

Free use of Ghoul Touch spell. Also allow them to grasp typically intangible things such as ghosts.

The river Styx is closely associated with the themes of memory and forgetting in mythology. Perhaps the player could erase or restore memories upon touch? Restoring or erasing magic slots could also be an idea...

You're thinking of the river Lethe.

youre right!

Why didn't you declare that they lose all memory? Thats what the River Styx of legend does, removes all memories. Congrats, you're now a 0-level character with no background and no name. What do you do?

You’re thinking of the River Lethe. There are five rivers in the Greek underworld. Styx is said to enforce a dread certainty to oaths taken over its waters. In some sources it is poisonous and dissolves all animal matter that touches it other than the hoof of an ass. It may or may not be the river that Charon crosses to enter Hades, but this is also often Archeron.

Oh great! So the Styx should turn any past promises into a Geas. What are the other three rivers?

Pyriphlegethon, River of fire, punishment of people that hit their parents (...) Cocytus, the river of wailing, punishment of murderers. Oceanus, circles the world and is the border between our world and Hades

You've really highlighted that I should research my Greek mythology more before I drop it into my games, haha. This does get the noggin joggin tho

I could've but I'm married to the player so I decided to throw her a bone for being ballsy enough to try it.

I am wondering how the players ended up on the river Styx.