Suffusion confusion

[phantasm]

I was working on a project weapon and it was ready for an S3 cast. My clerics skill was not enough to do it 100%. Suffuse estimate showed I would need to suffuse 75 points to get a 100% chance of success.

I happened to have 25 points of suffused energy and then started to question whether it was more cost efficient to use the 25 points to get a 50% chance of success, or just to cast multiple times with the 25% chance.

Failures would only cost 10k devotion without suffusion. If I suffused and cast the failures would be costing me 15k devotion.

So I did the math and it looks like its cheaper to just make the multiple casts with the 25% success rate instead of burning up suffused energy trying to get a 100% success rate.

I think in general suffused energy should only be used to reach new heights and make a cast that has 0% success rate possible.

Anyone else looked at the numbers on this system?

25% success rate (no suffusion): 100 casts = 25 successful, cost per success = 130,000 devotion
50% success rate (25 suffused): 100 casts = 50 successful, cost per success = 165,000 devotion
100% success rate (75 suffused): 100 casts = 100 successful, cost per success = 250,000 devotion


I'm not great at math, maybe I setup the scenario incorrectly? Should I instead look at how many casts it takes to make 100 success for each rate?

[Tgo01]

Your math looks right, but there are a couple of things to keep in mind.

Over a long enough period (like 100 casts as you point out) it would average out to 4 casts needed for a successful cast, but on a per project basis it won’t necessarily average out like this. It could end up taking a dozen casts before you are successful, which would put it on par with the 100% suffuse route.

Also I think it’s largely a psychological thing for many people. Having a failure feels like wasted energy, whereas using suffuse feels like you’re putting the energy to good use.

Also if it’s a situation where someone is buying the service from someone else the seller might not necessarily want to try the same cast 10 times each with a 15 second roundtim, which just occurred to me that might be why they put such a long cooldown on this spell to discourage someone from just trying over and over again when they just have a 5% success rate or something.

[Izzy]

You could offset it a bit further with Gift of Eonak, which grants you a second roll for each service attempt and takes the better of the two. I agree with Tgo01's analysis overall. For a personal project I'm willing to teeter on less-than-perfect success chances with a few attempts, but if providing a service for another I would not make the same risks in the interest of completing the deal.

[Archigeek]

Pretty sure Tsalin went through the math in this a while back. I think it makes sense to go with the odds on lesser projects, but as the potential loss gets higher, and the pool of casts to average your risk over gets smaller, it makes a lot less sense to take risks.