Query, currently trying to work out the maximum Psy rating that a psyker can possibly attain when attacking.

Assumptions:

Rules on the PR talent say that it is rated on a scale of 1-10. Now it has to be possible to exceed this as otherwise the Push ability when casting would be mostly pointless, and there are also powers which require this to be pushed. Otherwise it means you have to push the power for no extra gain but all the extra risk. If there is something which says otherwise then this will be considered a hypothetical experiment.

I am disregarding consequence of the paths to power such as extra phenomenon, penalties on the phenomenon roll etc. These are not an issue at the moment.

Acquisition or limitations on gear is not considered an object. I'm in GM mode and I have a clean XP/Infamy credit card

So, is anyone able to verify the below calculations and identify if there are items/talents missed?

Maximum Buyable PR: 10

Unbound Push: +5

Blasphemous Incantation: +1

Child of the Warp: +1

Warp Conduit: +1d5

I calculate so far a theoretical maximum of PR22

You might also get mark of tzeentch, and PR-increasing gifts from him. Also, there is a ritual which increases everyone's PR in the area.

This actually isn't anywhere near the maximum psy rating attainable if you take into account Protean Form and Boon of Tzeentch.

In fact, depending on how you read the RAW Protean Form and Boon of Tzeentch can be chained to attain essentially infinite potential psy rating on any power you couple to Boon of Tzeentch. Of course, any sane GM would rather quickly shut this infinite power loop down.

Boon of Tzeentch grants extra psy rating on the next unfettered or pushed power you cast equal to degrees of success on the BoT Focus Power WP activation roll. Protean Form grants 2*psy rating in unnaturals to a characteristic of your choice (or miscellanous bonuses that are usually worse). If you throw all the unnaturals from Protean into Unnatural WP, cast a Boon of Tzeentch with all the extra DOS's from your Protean Form unnatural WP, and then recast Protean Form, you can increase your unnatural WP indefinitely and thus your effective psy rating on your next Boon of Tzeentch boosted power (eventually the damage from Boon of Tzeentch's backlash will kill you or stun you out of your loop so you do also want to either deviate some of your Protean Form unnaturals to Unnatural Toughness or simultaneously maintain and boon of tzeentch recast telekinetic shield or whatever it is called in BC to keep your soak up).

Even if we don't allow for this goofy exploit, the potential power from this coupling is still staggering. First, cast Boon of Tzeentch full push at effective psy rating 21(MoT makes you a Bound Psyker but if you are on D-Dust you are a Daemonic Psyker, and so can still push up to 4). Assume that you roll a 1 and have Unnatural WP (2) (from MoT and the Chaos Organ mutation). Assume that you are a Thousand Sons Sorcerer who rolled maximally on their starting WP and also picked all the background/personality stuff that boosted WP and has purchased all WP advances (I think you can get up to 81 base WP this way,but it's been a while since I have checked) and who is dual wielding (you can get more with multiple arms but let's not go there) Lord of Change-bound Daemonweapons with the property that adds twice the Daemon's WP bonus to your focus power tests (+32 in total), has a psy focus (+10), and a psychic hood (+5), are using the Fate Loom Power (+20), and are on the drug Manic (+30). This should get you something like 283 effective willpower (factoring in the +105 from your 21 effective psy rating for the focus power). I can't recall if bonuses to tests are capped in BC- if they are, then you are only at +60 and so have a pitiful 141 effective willpower. You can also throw in a maintain Psyphon for an added Unnatural WP (5) (assuming best possible roll on the wp damage).

Your total Unnatural WP of 7 gives you 3 DOS's on the power activation, plus the 15 to 29 or so DOS's from rolling a 1 on the above. The total boost to your psy rating should be around 18 to 32 as far as your next power is concerned. This can allow you to get on a full pushed Protean Form (not a great idea, but hey) 39 to 53 effective psy rating, giving you 78 to 106 or so effective Unnatural WP. On your next Boon of Tzeentch'd full push power (assuming you have the soak and wounds needed to survive using a Boon of Tzeentch with that many DOS's and that you roll a 1), you'll have around 55 to 85 or more added psy rating (I mean you can maintain Psyphon for a -1 psy penalty but for the extra BoT DOS's, you can maintain telekinetic barrier or deviate psy rating from unnatural WP to not die to Boon of Tzeentch, etc. allowing for a fair bit of variation) plus the 21 you are getting just from maximum pushing.

You obviously want to use Ritual Slaughterer to avoid incapacitating or killing yourself with the many, many Perils you are invoking in doing this.

So yeah, maximum effective psy rating is probably somewhere between 70 and 100 if you read or rule that you can't infini-chain BoT and PF (and also happen to roll 20 on psyphon, and two successive 1's on Boon of Tzeentch, which is very unlikely). Even if you ignore all this absurdity a full pushed BoT can still give you a massive amount of extra psy on an average roll, and given that you are psy rating 10 so too can an unpushed one. Basically, an apex-tier sorcerer of Tzeentch using everything at his disposal can via the BC rules more or less wipe out an entire titan legion with one Force Storm usage, if these calculations are anywhere near correct (I suspect that a 100d10 Bolt of Tzeentch might also be capable of taking out starships but I'm not sure what the ground to space damage and soak conversions are if they were ever provided in RT). Let us not speak of coupling this with Warptime and crushing blow lightning attacks dual-wielding force swords with killing will activated each strike (admittedly you aren't going to Boon of Tzeentch the Killing Wills, but you're still felling multiple Titans in melee per round, assuming that it's actually physically possible to be in melee with more than one at any given time). Stack this with Daemon Legacy whatever weapon properties for even more entertainment value (If we're going to the maximum possible we may as well go all the way with everything).

The Rite of Sundering from Tome of Fate and Spook from Tome of Excess can both increase your psy rating by 2 for the duration of their effects but I'm not clear as to whether this will have any benefit if your psy rating is already 10. If so, you can rock around this Boon of Tzeentch stuff with effective psy rating 25 and get even more egregious with your psy rating by a little bit. I don't think that MoT and Warpsmith can actually increase your permanent psy rating above 10.

Note one added potential caveat- Protean form does IIRC require Corpus Conversion, which may not be purchased, if I read the talent rules correctly, by CSM characters. If this holds, you either keep the TS Sorcerer and his 81 WP and throw out the benefits of Protean Form, or you make it a Rogue Psyker with a piddling 76 WP (which alters the exact numbers either way). My math might also be off a bit with some of the above calculations, but given the gratuitously large numbers involved anyway I don't think this is hugely important.

I recall Rogue Trader also having rules for an "Aetheric Wave Spar" or whatever augmetic that gave +1 to push results, as well as psychic familiars that could add extra psy when using certain kinds of powers or negate multiple maintain penalties. In the games in which I've played we usually throw open all WH40kRP books as far as NPC stats, items, backgrounds, and elite advances go (usually taking the most recent incarnation of anything that recurs in multiple books and taking everything from DH with a critical eye given the often ludicrous stats and balance present in that game line), but other groups might hew more narrowly to what has been publishd strictly for a certain game. There's probably more drugs and the like that can also boost WP rolls or effective psy rating in some other game line's supplements that don't come immediately to mind.

That is both terrifying and impressive in equal measures...and also welcome with it being a first post. The logic is sound but the numbers I'd need to go over more closely but I trust there being close enough with a slim margin of error. The concept of Warptime though with that high a PR is just nasty...GM hammer would step in to stop the chaining, I am also of course not wanting to be too mean.

The reason this has come up is that I'm trying to identify what possible PR different psyker levels (Alpha, Beta, Gamma etc) on the Assignment scale might compare to and what potential deals a player might have to do to match them. There are a few threads here and the debate seems open to interpretation.

The best we have to compare PR to alphabetical schale is an NPC from Acsention with PR 14 who is said to be approaching alpha-level potential.

To be fair, Dark Heresy is also characterized by stat blocks that are totally out of whack with how the rest of the systems tended to handle things and common sense (I am reminded of the Scarce availability Medicae Servitor from the Lathe Worlds with agility 40 and effective Medicae 100)- Ascension in particular had ridiculous things like the Vindicare Assassin AG bonus dodges per round and ability to dodge anything, being able to buy Unnatural WP x3 on Inquisitors and Primaris Psykers, etc. that were never reproduced in the other systems . It doesn't really make any sense to me that permanent psy rating 14 is "Alpha Minus" when Lords of Change, Daemon Princes, Chaos Sorcerers, etc. are in BC never depicted as being able to have psy ratings above 10- if 10 is the peak for those who are lords of the Warp and paragons of the Master of Magic and is the highest you can go in a high-power setting like Black Crusade, it feels like that should represent the apex of potential for anything short of a truly god-like psychic beings (Ascended Magnus the Red, the Emperor, the Eldar gods when they were still whole, etc.).

On that note, I've always thought that Greater Daemons were incredibly underwhelming psychically. Automatic 1d5 successes on focus power tests is pretty bad compared to what a high-WP psy rating 6-9 psyker can achieve on a typical focus power. In our games we usually just houseruled them to simply ignore any and all psychic phenomena and perils they invoked (keeping the AoE effects for those unfortunate enough to be in the vicinity), meaning that they could focus power and push to their heart's content and thereby readily match and surpass high-tier mortal psykers (as opposed to just being crushed in any opposed roll).

Well, a Greater Deamon is by no means the epitome of the scale, at last not in the fluff. They are incredible mighty beings but even they are not capable of the feats a Psyker anywhere around Alpha or even Alpha Plus could achieve. Above that? Think of the Apex Twins, being of absurd power if together they would have no reason at all to stick with some pesky annoying warband, even if that thing only consists of loyal Deamon Princes - they would be just toys.

But yea, it always depends on what source material you base your arguments on.

Oh, and by the way infinite PR is still impossible. RAW mentions that bonuses to anything coming from psychic powers never stack.

Well, the rulebook states: "Modifiers, Characteristic increases, and other benefits generated
by psychic powers do not stack—only the highest applies"

But this doesn't really seem to have any effect on being able to chain Boon of Tzeentch and Protean Form (even if you rule that Protean Form expires on attempting to cast a fresh Protean Form, the Unnatural WP from Protean Form has already been preserved as bonus Boon of Tzeentch psy rating from the preceding BoT cast) or accumulating a very high effective psy rating for a specific ast between Pushing and Boon of Tzeentch. It does mean you can't stack and stack things like Fate Loom, Psyphon, etc. into this to make things even easier and quicker, of course. Unless you referred to something else?

It also occurs to me that Corpus Conversion and Ritual Slaughterer give bonuses to the test or DOS's for the relevant psychic power, which could further enhance the efficacy of BoT abuse.

Wait a bit. No benefits must stack. At all. Both of those powers affect your ability to manifest powers. Both of them stack in your exploit. What else do you need as a GM to restrict the abuse?

Wait a bit. No benefits must stack. At all. Both of those powers affect your ability to manifest powers. Both of them stack in your exploit. What else do you need as a GM to restrict the abuse?

They don't really need to stack - you use the boost from BoT to cast Protean Form at insanely high PR, then use the boost from Protean Form to cast BoT at insanely high PR, then use the boost from the boosted BoT, etc. Each time you're switching out the bonus, I think. Or you could rule it that way to get round the 'no stacks' rule.

then use the boost from Protean Form to cast BoT at insanely high PR

And this is the place in "loophole" where stacking begins to occur and where GM should say stop.

As soon as there's a feedback loop stacking technically occurs.

then use the boost from Protean Form to cast BoT at insanely high PR

And this is the place in "loophole" where stacking begins to occur and where GM should say stop.

Actually it simply says all bonuses. As you're switching bonuses, that's not stacking. Stacking would be combining both bonuses.

>>benefits generated by psychic powers do not stack

Both of those benefit psychic power use. What else do you need FFG to write in the book to forbid this loop using RAW?

The statement in the rules only indicates that modifiers don't stack, so that you can't simultaneously get Unnatural WP (7) from Unnatural WP (3) and Unnatural WP (4) provided by separate powers, or simultaneously get +10 to all Perception rolls from one power and +20 from another for net +30. Added psy rating on a power and unnatural WP are completely distinct and unrelated things. They both happen to incidentally boost certain kinds of rolls (Focus Power rolls that are also Willpower based, which is not all psychic powers), but the benefits provided by the two are not of the same type (especially when considering that extra DOS's and extra psy rating usually modify different parts of a power's effects). Moreover, there's no need to simultaneously maintain Protean Form and have a completed Boon of Tzeentch already primed for your next power, so at any given time only one power needs to be providing its bonuses to your next cast, and you're always replacing the previous iteration of Protean Form with a new iteration based entirely off of the psy rating from your most recent cast. I don't really see how the wording can be considered to explicitly block this particular exploit, although common sense on the part of the GM certainly would.

It also occurs to me that there might be a somewhat more tortuous way of getting the same BoT-dependent loop by coupling Boon of Tzeentch with Glimpse and the Sacrifice path to power, given that you could BoT a Glimpse used to buff the Sacrifice Forbidden Lore: The Warp Test, and then apply the extra +5 per DOS from that test to a Boon of Tzeentch, apply that Boon to a new Glimpse, use that Glimpse bonus on a new Sacrifice, etc., which could allow you to terminate with one extremely powerful Boon of Tzeentch to generate one conceivably infinitely potent sustain or singular cast of a power (although this chain can be set back or interrupted by particularly bad rolls).

Nope, still stacking.

X benefit from BoT into X&Y benefit from Protean into another XXY benefit from BoT into XXYY benefit from Protean. It stops as soon as you've got two X's during the second cast of BoT. The benefits of the psychic power never goes away, and you can't stack the same benefits with eachother. It's a feedback loop.

In any case, any half-decent GM will identify the issue and disallow the (admittedly creative) attempt, even if they think it's allowed by RAW.

It doesn't work well with Glimpse as there's a -60/+60 cap on modifiers.

However there are examples of -70 modifiers such as for gear acquisition.

However there are examples of -70 modifiers such as for gear acquisition.

That's a special case, and has its own rules for modifiers.

True, just making a point.

In all these cases the GM would usually bring the hammer down quite quickly on this. Assuming it isnt counted as buff stacking, the numbers are theoretically insane. However if its classed as stacking it looks like this power combo would add roughly another 10-20 onto any other PR...

I wasn't defending it as a build - I was merely pointing out that the rule you were using to block it didn't block it. Any GM worth their salt would stop it anyway, and if it were me I'd have anyone trying it explode into so many daemons from trying to pull that much of the warp into reality. But it is legal according to RAW. Then again, according to RAW you can quite easily turn yourself into a walking Titan (Nurgle Sorcerer max PR wearing Best Termie Armour and Mechanicus Assimilation x10 (that's where I limit it but according to RAW it's technically infinite) with Personal Best Power Field casting Inviolable Flesh with the various mutations that make you Enormous with a Best Great Unclean One possessed Force Scythe and Blade of Baleful Might) but any GM within their right minds would stop this build as soon as it started.

As a side note, the above build (assuming best possible rolls in every single respect) would have Toughness 85, Unnatural Toughness (+17), the Chaos Organ (Unnatural Toughness +1 and Regeneration (1)), Grossly Fat, Corpulent Immensity and Winged (so he could move) Mutations, 25 AP, Forcefield Rating 80 with an Overload of 01, and an absolute minimum of 25 Wounds (though likely more as SC is Nurgle), and would deal 7d10+35R, Pen 20, Unbalanced, Felling (24), Force, Proven (22), damage with each scythe swing, which would get a +10 to each WS Test. With Lightning Attack, this automatically deals 180 odd damage up to 7 times in one attack. This, frankly, is stupidly overpowered.

I wasn't defending it as a build - I was merely pointing out that the rule you were using to block it didn't block it. Any GM worth their salt would stop it anyway, and if it were me I'd have anyone trying it explode into so many daemons from trying to pull that much of the warp into reality. But it is legal according to RAW. Then again, according to RAW you can quite easily turn yourself into a walking Titan (Nurgle Sorcerer max PR wearing Best Termie Armour and Mechanicus Assimilation x10 (that's where I limit it but according to RAW it's technically infinite) with Personal Best Power Field casting Inviolable Flesh with the various mutations that make you Enormous with a Best Great Unclean One possessed Force Scythe and Blade of Baleful Might) but any GM within their right minds would stop this build as soon as it started.

As a side note, the above build (assuming best possible rolls in every single respect) would have Toughness 85, Unnatural Toughness (+12), the Chaos Organ (Unnatural Toughness +1 and Regeneration (1)), Grossly Fat, Corpulent Immensity and Winged (so he could move) Mutations, 25 AP, Forcefield Rating 80 with an Overload of 01, and an absolute minimum of 25 Wounds (though likely more as SC is Nurgle), and would deal 6d10+45R, Pen 20, Unbalanced, Felling (20), Force, Razor Sharp, Shocking, Tainted, Tearing, Toxic (8) (dealing 2d10 Toughness damage and making target carrier for 7 Rounds), Warp Weapon damage with each scythe swing, which would get a +10 to each WS Test. This, frankly, is stupidly overpowered.

You missed a trick, legacy weapon with that scythe as well as the binding you mentioned. Since we're going for ultimate levels of cheese of course...

I wasn't defending it as a build - I was merely pointing out that the rule you were using to block it didn't block it. Any GM worth their salt would stop it anyway, and if it were me I'd have anyone trying it explode into so many daemons from trying to pull that much of the warp into reality. But it is legal according to RAW. Then again, according to RAW you can quite easily turn yourself into a walking Titan (Nurgle Sorcerer max PR wearing Best Termie Armour and Mechanicus Assimilation x10 (that's where I limit it but according to RAW it's technically infinite) with Personal Best Power Field casting Inviolable Flesh with the various mutations that make you Enormous with a Best Great Unclean One possessed Force Scythe and Blade of Baleful Might) but any GM within their right minds would stop this build as soon as it started.

As a side note, the above build (assuming best possible rolls in every single respect) would have Toughness 85, Unnatural Toughness (+12), the Chaos Organ (Unnatural Toughness +1 and Regeneration (1)), Grossly Fat, Corpulent Immensity and Winged (so he could move) Mutations, 25 AP, Forcefield Rating 80 with an Overload of 01, and an absolute minimum of 25 Wounds (though likely more as SC is Nurgle), and would deal 6d10+45R, Pen 20, Unbalanced, Felling (20), Force, Razor Sharp, Shocking, Tainted, Tearing, Toxic (8) (dealing 2d10 Toughness damage and making target carrier for 7 Rounds), Warp Weapon damage with each scythe swing, which would get a +10 to each WS Test. This, frankly, is stupidly overpowered.

You missed a trick, legacy weapon with that scythe as well as the binding you mentioned. Since we're going for ultimate levels of cheese of course...

Please. That'd be stupid. Of course, my centauroid Berserker sniper build is even more ridiculously cheesy, but that's for another thread.