Help designing a power?

[Desthro]

GURPS: Powers is just what the doctor ordered.
I would build a power using GURPS: Powers (page 9 is where the bulk of this process starts.) I'm sure that there are countermeasures that could be taken, but I'll let you delve into that and assign an appropriate power modifier.

Originally Posted by jj234

Description of Initial Power: Some magical sand that is utilized by one of the characters in my campaign, is given limited sentience. It's only job is to protect the character from any harm that comes his way (even if he wants to harm himself). Whenever attacked a dash of sand will come up to interrupt the strike. It's pretty much a living shield of sand.

This is Damage Reduction. That is the easiest and quickest way to go about this. How it looks is largely fluff. You will tack on your power modifier and if there is any type(s) of damage that the DR cannot prevent you would apply it here as well.

Originally Posted by jj234

Description of Advanced Power:If the character chooses, his sand can be given the power to resist heat.

DR fits the bill here as well. You can apply a limitation on the DR from Stage 1 to prevent it from stopping heat-based damage. You might also include Temperature Tolerance if the sand allows the character to endure higher environmental temperatures.

Originally Posted by jj234

then the power to become superheated

I'm assuming you would use this for various innate attacks with the appropriate modifiers. Creating an innate attack with alternate versions is easily managed here. Tack on your power modifier and any appropriate limitations for the most expensive ability, then price all other abilities that are similar or related at 1/5th of their total cost.

Originally Posted by jj234

then the power to become explosive, then the power to become an incendiary explosive and finally the sand may gain the properties of a white-phosphorus like explosive.

You can add additional alternative abilities as you see fit and re-price the package accordingly if one of the abilities becomes more expensive than the rest.

Originally Posted by jj234

In addition to this, the projectiles shot up by the living shield's explosions will leave sticky and smouldering incendiary residue on the attacker's weapons (or arm). And if that wasn't stupidly overpowered enough already, there shall be a 5ft radius around the character which shall act as a mine field, exploding whenever someone who isn't the character steps on it. Keep in mind that the sand is explosive on command and won't naturally explode unless willed by the character.

Just another power to build for this character's power set. An Innate Attack with the Aura modification covers the incendiary residue stuff, and an Innate Attack with AoE and Emanation with a selective Area would cover the last one, though I'm sure there are dissenters.

If you want specific help with Powers, PM me and I'll give you my E-mail address.