Psi powers and skills
 

So if making a Psionic and doing a set of powers.

So doing a TK bullet and hitting a man sized target which is the correct procedure:

I: Roll to manifest the power, with penalties to hit the target.

Or

I: Roll to manifest the power.
II: Roll vs innate attack to hit the target.

The manifest power skill for for example TK bullet is a IQ/hard skill. It's just if I need the innate attack or I do this when manifesting the power.

Re: Psi powers and skills
 

Based on the ability (which has 'based on IQ' as a modifier) and the total absence of the Innate Attack skill in GURPS Psis, I don't think Innate Attack is relevant.

It might, however, be the second case with the TK Bullet skill used in the second roll instead of Innate Attack. Considering the costs of failing a manifestation, and the strangeness of being more likely to suffer them if tossing pebbles at small or distant targets, I'd be strongly inclined to this interpretation.

Re: Psi powers and skills
 

As the ability states, "Take an Attack maneuver and make a skill roll, with all normal modifiers for the ranged attack." Because there's no mention of a second skill roll, you only roll once, and it's to attack. If you fail the roll, you miss, but the bullet still goes somewhere.

That said, if the GM prefers to interpret a failed roll as "your ability didn't even manifest," that's fine too, but it isn't the default assumption.

Re: Psi powers and skills
 

If there's no manifestation roll, does that mean there's no opportunity for a power-injuring critical failure?

Re: Psi powers and skills
 

I am not using GURPS psionic powers, but my own psi powers. So feel free to ignore this.

In it I have a few different types of psionic powers.

General powers work as normal and all require a IQ/skill check to activate and usually at least one concentration action.

Attack powers are any power that are any sort of direct attack. These do not require concentration actions but can use any Attack manoeuvres. They do not require a skill check but an Innate Attack roll. However they all have a "malf" number equal to what their IQ/Skill would be.

Re: Psi powers and skills
 

No, you still check for that on a critical failure. Unless an ability says otherwise, all of the How Psi Works rules apply to it.

Re: Psi powers and skills
 

That means that ranged attack penalties like light level, concealment, range, and size get to contribute to breaking your powers...

And even just missing a shot means taking the repeated attempt penalties.

Re: Psi powers and skills
 

Ok so its number 1, thanks for the help.

Re: Psi powers and skills
 

Right. Penalties to your skill roll may* make it more likely that you'll critically fail, because that's how every skill works in GURPS. It doesn't matter where the penalties come from. If you're trying to do something very difficult and tricky with your psi, you're accepting a greater degree of risk.

* In practice, this only happens when your skill (A) drops from 16+ to 15 or less, or (B) drops from 7+ to 6 or less.

Yep.

Mind you, if you prefer to separate TK Bullet (along with all other "Attack" abilities!) into a two-roll process, that's a perfectly viable house rule. Just be consistent across the board and there shouldn't be any significant balance issues.

Re: Psi powers and skills
 

In my house rules, I also use a single roll, but I only apply the normal psi modifiers to the roll to see if it manifests or not (so a failure with only those modifiers means a repeated attempt, and it determines if it's a critical failure to manifest or not, etc.), and, assuming it successfully manifested, I then also apply the combat-only modifier (lighting, range, cover, etc.) to see if it the bullet hits the target. Failure to hit the target does not trigger a repeated attempt effect.

Re: Psi powers and skills
 

That's how I do it. I found TK Bullet became too likely to fail otherwise (and thus overly subject to the repeated attempt penalties).