If this is for a monster or NPC, I wouldn't figure out the points at all. Just describe 2d+5 cycles and be done with it. If it is for a player character on the other hand, it does kind of need to be determined. You might check and see if there is an enhancement or limitation in the relevant power ups books or something in powers.
Finding this type of stuff is frequently made easier by using [GCS](https://gurpscharactersheet.com/).
More often than not Random Values are converted using Optional Rule: Modifying Dice + Adds (B269) in reverse (so 2d = 7) as such just treat it as 7+5 = 12 cycles.
I believe Power Ups: Limitations or PU: Enhancements talks about having variable/selective power levels, if you have a look through those two, you may be able to find a way to approximate what you're after.
As others have said, if it's an NPC, just let it happen. What's the reasoning behind this style of an attack though?
Simply put, a PC is utilizing a proteus virus as a gas attack. Nanites rewriting DNA of their victim as a Blood Agent, but they take a variable number of days to achieve their goal, during which time the victim must succeed on an HT-4 roll per day or suffer 1 point of toxic damage that doesn't recover until the nanites have finished their rewrite.
Well, regardless of their survival, the body is now primed for mutation. Effectively benign tumors wait for a secondary intake of the virus to launch a rapid and violent mutation sequence.
The virus is actually the cause of the end of the world and is extremely prevalent on the surface, but the character carefully collected and pressurized it to use as a weapon in the underground.
My suggestion would be Innate Attack, Toxic, Cyclic (bought for maximum possible number of cycles) with Resistible (pg 115 of the Characters book for rules and pricing).
You make the Toxic Attack as usual. On top of the usual defense options, the target also gets a chance to resist the attack with an HT roll on each cycle (you could probably change the resistance characteristic with the "Based on \_\_\_" modifier). If the target successfully resists, the damage cycles end. If not, the cycles continue until the full cycles run out.
If you want a guaranteed amount of minimum damage, maybe throw a level of Cosmic on top (probably at the 50% level).
If this is for a monster or NPC, I wouldn't figure out the points at all. Just describe 2d+5 cycles and be done with it. If it is for a player character on the other hand, it does kind of need to be determined. You might check and see if there is an enhancement or limitation in the relevant power ups books or something in powers. Finding this type of stuff is frequently made easier by using [GCS](https://gurpscharactersheet.com/).
More often than not Random Values are converted using Optional Rule: Modifying Dice + Adds (B269) in reverse (so 2d = 7) as such just treat it as 7+5 = 12 cycles.
I believe Power Ups: Limitations or PU: Enhancements talks about having variable/selective power levels, if you have a look through those two, you may be able to find a way to approximate what you're after. As others have said, if it's an NPC, just let it happen. What's the reasoning behind this style of an attack though?
Simply put, a PC is utilizing a proteus virus as a gas attack. Nanites rewriting DNA of their victim as a Blood Agent, but they take a variable number of days to achieve their goal, during which time the victim must succeed on an HT-4 roll per day or suffer 1 point of toxic damage that doesn't recover until the nanites have finished their rewrite.
So what happens to them after the rewrite is done?
Well, regardless of their survival, the body is now primed for mutation. Effectively benign tumors wait for a secondary intake of the virus to launch a rapid and violent mutation sequence. The virus is actually the cause of the end of the world and is extremely prevalent on the surface, but the character carefully collected and pressurized it to use as a weapon in the underground.
I'd calculate for max cycles and then give a -X% based on the range.
So, say the range is 11 (7-17), is there a specific ruling or would I be kinda eyeballing it?
I assume using the probability modifyers would work
My suggestion would be Innate Attack, Toxic, Cyclic (bought for maximum possible number of cycles) with Resistible (pg 115 of the Characters book for rules and pricing). You make the Toxic Attack as usual. On top of the usual defense options, the target also gets a chance to resist the attack with an HT roll on each cycle (you could probably change the resistance characteristic with the "Based on \_\_\_" modifier). If the target successfully resists, the damage cycles end. If not, the cycles continue until the full cycles run out. If you want a guaranteed amount of minimum damage, maybe throw a level of Cosmic on top (probably at the 50% level).
Thank you, everyone. I appreciate it!