How to Use Psychic Senses of Psi-Stalkers and Dog Boys?

[Hotrod]

I've been working on some NPC generators for Psi-Stalkers and Dog Boys, and I realized a short while ago that the mechanisms by which they actually hunt prey confuse me.

Take the first example from the Psi-Stalker's Sense Psychic and Magic Energy description in RUE, p153: "If a human psychic (Minor, Major, or Master) enters the room, the Psi-Stalker will instantly sense it, as well as be able to trace it to the specific individual."
The way I read it, the sensing is automatic. What is meant by "able to trace it?" Is the tracing also automatic, or does it require a skill roll? If it requires a roll, which skill roll is used? The first one mentioned is 20% + 5% per level of experience, but that's in the next paragraph, which focuses on recognizing and tracking a specific psychic scent. The next one, 60%+5% per level, is used specifically for tracking down someone who has used his/her powers within detection range of the Psi-stalker. To make matters more confusing, this second skill mentions that the character may recognize the scent later, and gives the 20% + 5% per level skill again.

Also, how often is a tracking roll required? The same passage says every melee and every 1000 feet, and doesn't specify which criteria applies to which type of situation.

Let's try walking through a slightly more illustrative example than what's in RUE:

1. A Psi-Stalker is totally alone, with no psionics, magic users, supernatural creatures, or ley lines within four miles. A psychic comes within 50 feet of him without activating a power. Per the canon example, the Psi-stalker auto-detects the psychic. Is a roll required to locate the psychic? If so, does the psychic have to re-roll every melee, or every 1000 feet?

2. Now a magic user enters the Psi-Stalker's detection range without activating a power, so that the magic user and the psychic are both within the stalker's range. Now the psi-stalker must distinguish between the two scents to track down a specific individual, so a roll is required at the 20%+5 per level. If the psi-stalker is hungry and doesn't care which one he tracks down, is a skill roll required?

3. The magic user moves out of the passive range of the Psi-Stalker and casts a spell, then starts running away. Now the Psi-Stalker can track the magic user at 60%, but the psi-stalker must the Psi-Stalker roll once every 1000 feet, or once every round/15 seconds? After the round in which the spell is cast does the Psi-Stalker continue to track the magic user, even if the magic user is not yet in the Psi-Stalker's passive range? If this pursuit takes a while, does it go back down at any point in time, or would the magic user have to escape from the Psi-Stalker's active detection range?

4. The magic user is now nearby the Psi-Stalker, and so is the psychic. If the psi-stalker wants to find the psychic, and not the psi-stalker, he'll have to roll his tracking skill at -10% due to the presence of an unrelated P.P.E. source. Is that % penalty also applied to the psi-stalker's ability to sense the presence of the psychic, so that it goes from automatic to 90%?

Then there's Sensing the Supernatural. The "Base skill" is 40% +5% per level, but then it says "Tracking by psychic sense alone is "30% + 5% per level when in disguise and not using its abilities." However, if it's a major supernatural being or it is actively expending P.P.E. or I.S.P., then the tracking skill is 70% + 3% per level. Those last two percentages seem to cover everything, so what is the point of the "Base skill?" Also, if it is, as the description says, "identical in function to the previous ability," then is the psi-stalker automatically able to detect the presence of a supernatural being? Is a roll required to locate such a being if it's within the passive range and there are no other magic/psychic sources?

I have other questions about the relative abilities of Psi-Stalkers vs Dog Boys, but I think I've asked enough for one post.

[Ed]

I've been working on some NPC generators for Psi-Stalkers and Dog Boys, and I realized a short while ago that the mechanisms by which they actually hunt prey confuse me.

Take the first example from the Psi-Stalker's Sense Psychic and Magic Energy description in RUE, p153: "If a human psychic (Minor, Major, or Master) enters the room, the Psi-Stalker will instantly sense it, as well as be able to trace it to the specific individual."
The way I read it, the sensing is automatic. What is meant by "able to trace it?" Is the tracing also automatic, or does it require a skill roll? If it requires a roll, which skill roll is used? The first one mentioned is 20% + 5% per level of experience, but that's in the next paragraph, which focuses on recognizing and tracking a specific psychic scent. The next one, 60%+5% per level, is used specifically for tracking down someone who has used his/her powers within detection range of the Psi-stalker. To make matters more confusing, this second skill mentions that the character may recognize the scent later, and gives the 20% + 5% per level skill again.

Also, how often is a tracking roll required? The same passage says every melee and every 1000 feet, and doesn't specify which criteria applies to which type of situation.

Let's try walking through a slightly more illustrative example than what's in RUE:

1. A Psi-Stalker is totally alone, with no psionics, magic users, supernatural creatures, or ley lines within four miles. A psychic comes within 50 feet of him without activating a power. Per the canon example, the Psi-stalker auto-detects the psychic. Is a roll required to locate the psychic? If so, does the psychic have to re-roll every melee, or every 1000 feet?

2. Now a magic user enters the Psi-Stalker's detection range without activating a power, so that the magic user and the psychic are both within the stalker's range. Now the psi-stalker must distinguish between the two scents to track down a specific individual, so a roll is required at the 20%+5 per level. If the psi-stalker is hungry and doesn't care which one he tracks down, is a skill roll required?

3. The magic user moves out of the passive range of the Psi-Stalker and casts a spell, then starts running away. Now the Psi-Stalker can track the magic user at 60%, but the psi-stalker must the Psi-Stalker roll once every 1000 feet, or once every round/15 seconds? After the round in which the spell is cast does the Psi-Stalker continue to track the magic user, even if the magic user is not yet in the Psi-Stalker's passive range? If this pursuit takes a while, does it go back down at any point in time, or would the magic user have to escape from the Psi-Stalker's active detection range?

4. The magic user is now nearby the Psi-Stalker, and so is the psychic. If the psi-stalker wants to find the psychic, and not the psi-stalker, he'll have to roll his tracking skill at -10% due to the presence of an unrelated P.P.E. source. Is that % penalty also applied to the psi-stalker's ability to sense the presence of the psychic, so that it goes from automatic to 90%?

Then there's Sensing the Supernatural. The "Base skill" is 40% +5% per level, but then it says "Tracking by psychic sense alone is "30% + 5% per level when in disguise and not using its abilities." However, if it's a major supernatural being or it is actively expending P.P.E. or I.S.P., then the tracking skill is 70% + 3% per level. Those last two percentages seem to cover everything, so what is the point of the "Base skill?" Also, if it is, as the description says, "identical in function to the previous ability," then is the psi-stalker automatically able to detect the presence of a supernatural being? Is a roll required to locate such a being if it's within the passive range and there are no other magic/psychic sources?

I have other questions about the relative abilities of Psi-Stalkers vs Dog Boys, but I think I've asked enough for one post.

IMO you’re getting too hung up with the semantics. The passive sense give the psi-stalker the ability to tell something is there and a rough idea where it is. The only time a tracking skill check is needed is if he’s trying to do something specific: recognize someone he’s met before, pick someone out of a crowd, or follow someone without using his other senses. In your examples the ‘stalker could just look at the target and follow it.

[Hotrod]

(snip)

IMO you’re getting too hung up with the semantics. The passive sense give the psi-stalker the ability to tell something is there and a rough idea where it is. The only time a tracking skill check is needed is if he’s trying to do something specific: recognize someone he’s met before, pick someone out of a crowd, or follow someone without using his other senses. In your examples the ‘stalker could just look at the target and follow it.

You're absolutely right about the semantics. The reason I'm getting so hung up on them is the nature of my NPC generators. I try to capture the essential abilities in as small a space as possible, so I'm trying to understand exactly which % I use for which scenarios and abilities. My goal is to try to reduce the prep time or guesswork for GMs. It's hard to do that when I myself don't understand the purposes of the many % values in these abilities.

In this scenario, I didn't say whether or not the stalker had direct visual contact with either the magic user or the psychic. Is scent recognition automatic within direct line of sight, as long as the subject is within the appropriate detection range?

[eliakon]

I would say that in some ways...
...this is like the "Pilot Auto" skill.
You don't actually need to roll against it to drive to work every day. Which is good because otherwise most drivers would be dead.
Instead the skill% is there for when there is a challenge or difficulty.
And yes I know that isn't very clear or the most helpful.
*thinks*
If I had to describe it for a generator I would put the %s in then a notation like "While these skills and their levels are provided, it can usually be assumed that like language skills, or driving that under normal routine circumstances they are not rolled against, hence the references to automatically succeeding."

[Axelmania]

Since mag and psi are lumped together in a single ability I think they only know SOMETHING is there, and will need to spend ISP on the more specific sense magic / sense psionics powers to discern which thing it is.

[Hotrod]

Since mag and psi are lumped together in a single ability I think they only know SOMETHING is there, and will need to spend ISP on the more specific sense magic / sense psionics powers to discern which thing it is.

The tracking ability is stated in RUE to cost nothing and always be on. That aspect of these abilities' descriptions is unambiguous and explicit.

[Hotrod]

I would say that in some ways...
...this is like the "Pilot Auto" skill.
You don't actually need to roll against it to drive to work every day. Which is good because otherwise most drivers would be dead.
Instead the skill% is there for when there is a challenge or difficulty.
And yes I know that isn't very clear or the most helpful.
*thinks*
If I had to describe it for a generator I would put the %s in then a notation like "While these skills and their levels are provided, it can usually be assumed that like language skills, or driving that under normal routine circumstances they are not rolled against, hence the references to automatically succeeding."

Well, let's turn it around, though, and consider the perspective of the supernatural being, psychic, or magic user in CS territory, like in the Burbs. There are a lot of them, from what I understand. If it's so easy/automatic to track them down, one might think that it would be impossible to escape capture. If player characters are attempting to avoid getting caught, I'd prefer to give them some kind of a chance at hiding or sneaking their way out.

Additionally, if Psi-Stalkers are indeed better at tracking than Dog Boys, then the practical mechanics should reflect that. Whether they actually are in the rules as written is somewhat debatable.

[Axelmania]

Since mag and psi are lumped together in a single ability I think they only know SOMETHING is there, and will need to spend ISP on the more specific sense magic / sense psionics powers to discern which thing it is.

The tracking ability is stated in RUE to cost nothing and always be on. That aspect of these abilities' descriptions is unambiguous and explicit.

Yup. They can track a scent. To discern what the scent represents though, I like them needing to spend the ISP.

Once they do though, they can remember the smell and know it belongs to a particular shifter they Sense Magicked years ago. They could not transfer the benefit to other dog Boyd without an article of sweaty hair follicles.

[eliakon]

I would say that in some ways...
...this is like the "Pilot Auto" skill.
You don't actually need to roll against it to drive to work every day. Which is good because otherwise most drivers would be dead.
Instead the skill% is there for when there is a challenge or difficulty.
And yes I know that isn't very clear or the most helpful.
*thinks*
If I had to describe it for a generator I would put the %s in then a notation like "While these skills and their levels are provided, it can usually be assumed that like language skills, or driving that under normal routine circumstances they are not rolled against, hence the references to automatically succeeding."

Well, let's turn it around, though, and consider the perspective of the supernatural being, psychic, or magic user in CS territory, like in the Burbs. There are a lot of them, from what I understand. If it's so easy/automatic to track them down, one might think that it would be impossible to escape capture. If player characters are attempting to avoid getting caught, I'd prefer to give them some kind of a chance at hiding or sneaking their way out.

Additionally, if Psi-Stalkers are indeed better at tracking than Dog Boys, then the practical mechanics should reflect that. Whether they actually are in the rules as written is somewhat debatable.

In the case of the Burbs in my opinion... what saves them there is that there are so many of them.
This is why when the CS is out on patrol they are so amazingly good at finding, tracking and destroying mages and psychics and yet at home they can't seem to do it. Because there are so many 'scents' overlapping in the Burbs that they DO need to try and make the skill rolls.
At that point it would be like any other use of the tracking skill (which again I know is hopelessly vague... but tracking isn't really well defined. My rule of thumb is that you roll every time there is a chance of loosing the trail such as a potential turn off, and every 5 minutes of walking or every other round of running. But that is my utterly unofficial house rule of thumb)
I don't think they are going to be able to totally hide (unless they can find a way to 'mask' their 'scent'...which sounds like an adventure right there to me!) but they can try to confuse the trail (cross their trail with other known scents, double back on their own trail, split up and regroup, make 'smell sinks (like an active spell) to walk through, have a mage ready to mystic portal you through some walls...all the usual things you see people do in the movies to throw off bloodhounds? Yeah do that sort of thing here to throw of the Psi Hounds.)

[Prysus]

I've been working on some NPC generators for Psi-Stalkers and Dog Boys, and I realized a short while ago that the mechanisms by which they actually hunt prey confuse me.

Take the first example from the Psi-Stalker's Sense Psychic and Magic Energy description in RUE, p153: "If a human psychic (Minor, Major, or Master) enters the room, the Psi-Stalker will instantly sense it, as well as be able to trace it to the specific individual."
The way I read it, the sensing is automatic. What is meant by "able to trace it?" Is the tracing also automatic, or does it require a skill roll? If it requires a roll, which skill roll is used? The first one mentioned is 20% + 5% per level of experience, but that's in the next paragraph, which focuses on recognizing and tracking a specific psychic scent. The next one, 60%+5% per level, is used specifically for tracking down someone who has used his/her powers within detection range of the Psi-stalker. To make matters more confusing, this second skill mentions that the character may recognize the scent later, and gives the 20% + 5% per level skill again.

Also, how often is a tracking roll required? The same passage says every melee and every 1000 feet, and doesn't specify which criteria applies to which type of situation.

Greetings and Salutations. Okay, I make it no secret I don't play Rifts, but I do read the material now and again for various reasons. I'll try to help the best I can, and you can weigh my answers accordingly.

For entering within 50 feet, I'd probably think of it something like Immortals from Highlander. You can automatically sense when the other enters into your range. They also seem to always know how to find the other. If within 50 feet, I'd say it's automatic. This is for two reasons. One, the text. Two, because unless the target is avoiding detection it's unopposed and a simple/normal task.

However, let's say a psychic or magic user enters into your range. The Dog Boy (or Psi-Stalker) lifts his head up and starts looking around. He makes his way through a crowd in the psychic's direction. The psychic makes a Perception check and notices the Dog Boy's approach. [Enter expletive here]! Instead of waiting for the Dog Boy to just walk up to him and grab him, the psychic starts to make his way out of the room (rushed, but not knocking over people to cause a scene). He makes it out into the empty hall and, now free from sight, makes a mad dash. Since he's made it out of the crowd first, the psychic clears more than 50 feet from him and the Dog Boy. Since the scent isn't as strong any more, the Dog Boy knows (or strongly suspects) his prey is fleeing. If he's fleeing, he must have good cause (someone innocent wouldn't run, right?). The Dog Boy can see the door the psychic left out of (he knows the direction he last sensed the psychic, and that's the only logical exit) and hurries through the crowd. He's now out into the hall as well. Left or right? The Dog Boy can attempt to track the psychic (tracking a specific scent, 20%+5% per level), or run down one of the halls and hope to get into range again. By the rules, the Dog Boy would have to roll again every 1000 feet until either the Dog Boy loses the scent (can continue to run in random directions hoping to get lucky, considering he didn't call for backup and there's others now searching for the psychic) or the Dog Boy gets within 50 feet again.

The Dog Boy loses the scent. Looks like the prey got away. Unfortunately for the poor psychic, he doesn't realize he's free yet. In a hurry to clear more distance, the psychic uses TK Leap to quickly clear a wall. If within 600 feet, plus 100 feet per level I'd say the Dog Boy gets a % roll (60%+5% per level) to sense the usage. If the Dog Boy succeeds, the chase is on again!

Let's try walking through a slightly more illustrative example than what's in RUE:

1. A Psi-Stalker is totally alone, with no psionics, magic users, supernatural creatures, or ley lines within four miles. A psychic comes within 50 feet of him without activating a power. Per the canon example, the Psi-stalker auto-detects the psychic. Is a roll required to locate the psychic? If so, does the psychic have to re-roll every melee, or every 1000 feet?

I'd say automatic (based on the text), as long as they remain within 50 feet.

2. Now a magic user enters the Psi-Stalker's detection range without activating a power, so that the magic user and the psychic are both within the stalker's range. Now the psi-stalker must distinguish between the two scents to track down a specific individual, so a roll is required at the 20%+5 per level. If the psi-stalker is hungry and doesn't care which one he tracks down, is a skill roll required?

See above.

3. The magic user moves out of the passive range of the Psi-Stalker and casts a spell, then starts running away. Now the Psi-Stalker can track the magic user at 60%, but the psi-stalker must the Psi-Stalker roll once every 1000 feet, or once every round/15 seconds? After the round in which the spell is cast does the Psi-Stalker continue to track the magic user, even if the magic user is not yet in the Psi-Stalker's passive range? If this pursuit takes a while, does it go back down at any point in time, or would the magic user have to escape from the Psi-Stalker's active detection range?

I'd say that you can follow it for the full 15 seconds (if the magic user is casting magic). However, once the magic user stops, and the 15 seconds elapses, you're back to your 1,000 feet rule. If the magic user continues to cast spells, the roll is once every 15 seconds. While this may mean the Psi-Stalker is rolling more often, he's rolling at a much higher percentage (40% more likely to find his target). Note: With average rolls and no extra skills that grant bonuses to Speed, a Psi-Stalker can move about 450 feet per melee round. That's 4D6+6 running, plus the Running skill automatic for an average Speed attribute of 30 (if I did my math right).

Note: I consider this much like firing off a big giant flare for the Psi-Stalker to follow. Even if you stop using magic, the Psi-Stalker will probably have a pretty good idea of where he last sensed the magic use.

4. The magic user is now nearby the Psi-Stalker, and so is the psychic. If the psi-stalker wants to find the psychic, and not the psi-stalker, he'll have to roll his tracking skill at -10% due to the presence of an unrelated P.P.E. source. Is that % penalty also applied to the psi-stalker's ability to sense the presence of the psychic, so that it goes from automatic to 90%?

A -10 penalty roll to something you don't roll is still something you don't roll.

Then there's Sensing the Supernatural. The "Base skill" is 40% +5% per level, but then it says "Tracking by psychic sense alone is "30% + 5% per level when in disguise and not using its abilities." However, if it's a major supernatural being or it is actively expending P.P.E. or I.S.P., then the tracking skill is 70% + 3% per level. Those last two percentages seem to cover everything, so what is the point of the "Base skill?" Also, if it is, as the description says, "identical in function to the previous ability," then is the psi-stalker automatically able to detect the presence of a supernatural being? Is a roll required to locate such a being if it's within the passive range and there are no other magic/psychic sources?

The Base Skill is like normal Tracking. You're looking for clues (things out of place, odd smells, a giant towering demon who stands taller than the rest of the crowd, etc.), amplified by your psychic scent. So when tracking (aided by psychic scent) you're at 40%. Basically the same way you'd track a human, only you get the benefit of psychic assistance. Note: If you can actually see the demon visually in a crowd, then you're not really tracking it, you're just following normal like any person with eyes can do.

If the demons is in DISGUISE (which means taking measures to blend in, such as metamorphosis), and the only way you can follow is through the psychic scent alone, then you're at 30%. So if you're looking at a police lineup (for example), and you can't tell who the demon is with any of your natural senses, you have a 30% chance using just this ability.

Then there's the more powerful demons and those actively using powers, which puts you at 70%.

As for why there can be so many in the 'Burbs, within 50 feet isn't that far of a range. If you're a psychic (not actually a crime, by the way), magic user, or supernatural being trying to avoid detection, then you do your best to avoid patrols. And, seriously, 1 in every 4 humans is a psychic. While the CS requires registration, I don't think that really applies too strongly in the 'Burbs (I could be wrong, not that familiar with the setting). So probably a thing of just ignoring the sensation unless there's a reason to start tracking.

I think that answers most of your questions, or at least to the best of my abilities (that's probably how I'd house rule it, at least). Hopefully some of that helped. Farewell and safe journeys for now.