On their current mission, my players will come across the aftermath of a Grey Knight purge of a daemonic incursion. One of the clues to what happened will be bolt casings everywhere, including some that are larger than others, made from silver, and etched with venerations of the Emperor. If I know my players, they will want to keep these, probably to sell.

Then I got to thinking: given the fact that Psicannon shells are impregnated with the aura of the Emperor, the spent shell casings may have some kind of game effect over and above their monetary value (I know that's not in the Rule As Written, which is why I'm not posting this in the Rules Questions section; I'm asking about 'fluff' interpretation). The only game effect that I can think of for them that doesn't blatantly turn them into 'magic items' is to count them as Lucky Charms- possibly limited to functioning against Daemons and Psychic Powers.

Can anyone think of a more 'colourful' use than that, which doesn't make them overpowered?

Bolter Shells are considered religious reliquaries and charms by the Imperium, so why not have them have a positive effect during social encounters if the players wear them about their persona?

As a follow up - how many bolter shells are we talking here?

I have not read so much Gray Knight lore again, so bear over with me if what I say isn´t totally true, but are the Gray Knights not a better kept secret for most in the Imperium? If that is true, would flashing their weird silver shells with odd writings on them not make them look like cultists or what there is worse instead of the good guys, maybe something to take into consideration no matter what other effects the shells are having.

A little bit off topic, I know, so sorry if this can´t be used to anything.

Hmm... yeah, they might add a bonus during a religious-themed Social-Encounter, or anything religiously themed. On the contrary, depending on how you run with the whole "Emperor is a divine entity" theme, you might want to penalize them for selling them... or allow them to donate them to the church to get rid of some corruption... or enhance faith-powers if you use them.

And, doomande, I think it really depends on how the casings actually look, since they might very well look quite "holy"... but on the other hand, yeah, they could also look quite heretical. But I'd think they look a bit more holy. Quite open to interpretation though, just like a lot in this setting.

I'd say make them a very minor psychic focus. If perils get rolled then like a -5 to the total. Making them a charm is a good idea. Social interaction boon with those who know what they are, likely higher ranking Ecclarisy, is a good idea too.

However having them might suggest the acolytes have larger connections than what are true, these "connections" can always bring about enemies.

I have not read so much Gray Knight lore again, so bear over with me if what I say isn´t totally true, but are the Gray Knights not a better kept secret for most in the Imperium? If that is true, would flashing their weird silver shells with odd writings on them not make them look like cultists or what there is worse instead of the good guys, maybe something to take into consideration no matter what other effects the shells are having.

A little bit off topic, I know, so sorry if this can´t be used to anything.

No.Grey knights using psycannon rounds isn't relevant at all in this scenario. The shell casing itself is still a bolter shell casing. If anything, anyone seeing them would probably think it's a sacred item

From Inquisitor's Handbook, page 208

Blessed Bolt Casing

Blessed bolt casings are common relics favoured by warriors and soldiers. Traditionally such casings come from the time of Drusus, used in the conquest of the sector. It is thought that any bolt casing used by a true-hearted warrior of the God- Emperor makes for a powerful charm. Blessed bolt casings are said to ward against the attentions of aliens and other foul creatures from the void. It is even said that presenting such a creature with the casing will strike fear into them and they will be unable look directly upon it. To attest to a casing’s holiness they often come with inscriptions engraved into the metal. These usually tell the tale of the casing—who fired it, where and when, and what it killed. The more auspicious the individual who used it and the greater the foe they slew, the greater the shell’s blessing. Some rare casings have been used more than once and have a detailed history scribed onto their shells telling of battles, heroes and confirmed kills.

As a follow up - how many bolter shells are we talking here?

There are lots of bolter shells- it was a ten-man squad of Grey Knights, sweeping a large section of a hive city- but I'll limit the number of Psycannon shells they find to something like 2d10 (probably more than they can carry, given the size/bulk).

I have not read so much Gray Knight lore again, so bear over with me if what I say isn´t totally true, but are the Gray Knights not a better kept secret for most in the Imperium? If that is true, would flashing their weird silver shells with odd writings on them not make them look like cultists or what there is worse instead of the good guys, maybe something to take into consideration no matter what other effects the shells are having.

Yeah, Grey Knights are super-secret, which means that almost no-one will recognize one of their Psycannon shells for what it is. To an average Imperial citizen, it's just a fancy silver vessel covered in religious script- which probably limits the impact it can have in social circumstances.

Blessed Bolt Casing

Blessed bolt casings are common relics favoured by warriors and soldiers. Traditionally such casings come from the time of Drusus, used in the conquest of the sector. It is thought that any bolt casing used by a true-hearted warrior of the God- Emperor makes for a powerful charm. Blessed bolt casings are said to ward against the attentions of aliens and other foul creatures from the void. It is even said that presenting such a creature with the casing will strike fear into them and they will be unable look directly upon it. To attest to a casing’s holiness they often come with inscriptions engraved into the metal. These usually tell the tale of the casing—who fired it, where and when, and what it killed. The more auspicious the individual who used it and the greater the foe they slew, the greater the shell’s blessing. Some rare casings have been used more than once and have a detailed history scribed onto their shells telling of battles, heroes and confirmed kills.

I was thinking that would be the effect of the regular casings, and the Psycannon ones would be better than that; but now that I think about it I guess the above description isn't meant to reflect all Space Marine bolt casings, so maybe that would be a good way to depict a Psycannon shell: permeated in the aura of the Emperor being roughly equivillent to a Saint's Relic...

Spitballing some ideas, in case you really want to go with mechanical benefits:

For every 10 bolter shells they keep and wear about their persons, they can give them a form of protection against daemonic entities - reduction of 'wound count' towards Warp Instability. What I mean here, is that normally a warp entity with that Warp Instability normally takes damage if it fails to cause wounds on a target each round. For every 10 psycannon shells in their possession, the psychic residue of the Golden Throne would be usfficient to deny +1 wounds towards that count.

I.e.

Random Daemon causes only 1 wound during the turn. Normally enough to ignore Warp Instability. Oh no, that guy he hit had 10 boltershells about his person. That 1 wound isn't good enough anymore! Daemon tests for instability.

This makes me think of an entire party of guys draped in ammo belts of spent psycannon shell casings, going "You can't touch this, daemon, neener neener".

This makes me think of an entire party of guys draped in ammo belts of spent psycannon shell casings, going "You can't touch this, daemon, neener neener".

"My face is my shield, my seal is my sword, spent shells are my armor!"

Overall though, Cognizar's idea is quite nice... maybe lower the necessary amount of shells needed for the effect (to make it less ridiculous) and we have something which, while not exactly OP, might give the players the one edge they need in that combat everything depends on... I might be exaggerating, but I think you know what I mean.

In all fairness, Gitsmasha's post was hilarious in the image depiction. I could just imagine a player saying that. =D

This makes me think of an entire party of guys draped in ammo belts of spent psycannon shell casings, going "You can't touch this, daemon, neener neener".

I'm dying laughing here, picturing Peter saying/singing this

http://www.youtube.com/watch?v=TLJN5ZdRMT4

I would allow them to be used as charms. I would also likely give them some bonus when used in meditation. If given to the right tech priest, (probably have to be somewhat radical to do this) they could possibly smelt it down and craft it into things which I would give minor bonuses when against daemons. Only problem is Im not sure what the casings are made off, and knowing the 40k universe, it could be very difficult to do so.