BlackHole Grenade

[LemmingLord]

I am running a one shot for someone who is considering using GURPS as his system to run "Mass Effect," something I know very little about. He wants a psychic power that allows him to create a point, a blackhole or singularity if you will, that draws everyone in the same direction..

I tried to run the numbers for telekinesis with area effect and it looks seriously expensive. How would you build it? Is there an accessibility limitation for "only one at a time" I might use?

Telekinesis Lvl 20 (20*5)=100+270%=370pts.
(or with multiplicative modifiers, hilariously, 100 +310%=410-40%=246pts) AE 4 yards +100%
Independent +40%
Persistent +40%
Wall (Sphere) +30%
Accessibility: only in one direction -40%

[Phantasm]

Powers, p. 83, lists Attraction as -60% when applied to Telekinesis. Repulsion is also -60%; Attraction/Repulsion is -30%.

So you were on the right track with -40%, but not enough of a discount, apparently.

[Nereidalbel]

It would probably be cheaper to use a Crushing Attack with Double Knockback and Feature: Reversed Knockback. Put Area Effect on that, and you get things knocked towards the center instead of away. It'll even match the game effect of causing damage at the same time!

[johndallman]

Originally Posted by LemmingLord

He wants a psychic power that allows him to create a point, a blackhole or singularity if you will, that draws everyone in the same direction.

I'd avoid allowing him to make actual black holes. That's likely to destroy the world, or if it doesn't, be very abusable.

[VariousRen]

Originally Posted by johndallman

I'd avoid allowing him to make actual black holes. That's likely to destroy the world, or if it doesn't, be very abusable.

Ya, an actual black hole comes with a whole bunch of "Real" problems. "The Krone Experiment" by J. Craig Wheeler is a sci-fi book centered around the idea that some scientists made mini-black holes. With a tiny amount of mass the hole has an almost invisible event horizon, but it consumes everything that comes within it. Because gravity is still a problem it drops to the center of the earth, and it's speed keeps it going out the other side. It repeats this, cutting bb sized holes through the earth and gradually slowing down from the drag of absorbing material. Given enough time it would settle to the core and the planet would slowly fall into it as the event horizon grew.

So hand wave the "Black hole" part as the common-person name, but it's actually a point attraction psychic hole or something, and the caster controls where it is when it's cast and stays relative to that location.

[quarkstomper]

There was an anime series back in the '80s, I think, called Silent Moebius about an elite squad of the Tokyo police trained to fight supernatural horrors. One of their weapons was a gun that shot depleted uranium slugs inscribed with spells that, when activated, would compress the slug into a micro black hole, so small that it would quickly evaporate into nonexistance, (at least I think that was the technobabble behind it), -- but which would last long enough to suck up cthuliod monsters -- as long as you timed the firing right.

[zoncxs]

I would do it as an area effect crushing attack with no wounding, double knockback, and double blunt trauma. It is a special effect that the knockback is reversed. The blast causes them to get pulled to the center, taking damage due to the acceleration (blunt trauma) and colliding with what ever is in the center. You can also link a corrosive attack to simulate things being sucked into a black hole. I can write it up when I get back home this week if you want.

[kdtipa]

I like the RAW recommendations, but just as an alternative: you could always go with a house rule. You'd be relying on your own ability to produce something balanced, but you'd define it so that its effects do exactly what you want.

This is totally off the top of my head, and I don't know any of the balancing factors in your campaign, but for example...

Implosion Field
10 points per level
You target a point in space, and while concentrating, everything around that point is pulled toward that point. Treat this as having a base ST score of 5 per level. Each yard away from center that a target is, reduce effective ST of the effect by 5. This effective strength determines whether the effect is strong enough to drag something toward the center (using normal encumbrance rules). It is also how the effect can be resisted. A ST contest can resolve whether a person can hold their ground or not. With an anchored object to hold on to, the target might have bonuses at the GM's discretion.

The speed of the pull is just one yard per second. A target in the field that wants to move away, has to win in a contest of ST again, and their own move speed is limited to one yard per second as well. Each yard away reduces the effect's ST, so it will get easier the further you get.

If something ends up in the center, that something starts taking crushing damage every second equal to the Thrust damage for the base ST of the effect. You can still make a contest of ST to make progress away from center on your turn. Each time an object takes enough damage to destroy it, reduce its volume by 10% until it reaches 10 times the damage necessary at which point you need a microscope to see the mass. For a person, the damage is the amount needed to automatically kill the target each time (so they would be dead before losing any volume).

When concentration stops, the effect ends, and all the matter that has collected at the center pops back to normal, causing an explosion that the same amount of damage it did to crush all the matter in the first place. So keep track of that. Like all other explosions in GURPS rules, each yard away from center means dividing the damage by 3 (so divide by 12 at 4 yards away).