1-2 First Strikes?

[CaptainHollister]

Hi all, relatively fresh Civ IV player here. Despite having this account for five years, I'm still very much a baby at the game.

There was something I noticed with a couple of units like the Navy SEAL and Skirmisher. Specifically (like the title says), the fact that they get 1-2 First Strikes. I understand the general FS concept, but not these specific numbers. Is there a probability that they get a second Strike, or do they get two on defence, or some other crazy third option? Thanks in advance.

 

[AcaMetis]

1-2 first strikes means they're guaranteed to get one, and have a chance at getting a second, on either offence or defence. What that chance is I have no idea though.

 

[Fippy]

Thread 'First Strikes'

Jan 31, 2009

First Strikes

This not really a strategy article; more an objective description of first strikes. Hopefully it will address the most common questions people have regarding first strikes.

It should be approached as a supplement to the more complete guide Combat Explained, written by Arathorn. The linked article is very comprehensive but oddly the details on first strikes are mostly glossed over, and the assumption put forward that first strike chances have 50% probability is incorrect.


What's the difference between first strikes and first strike...

• PieceOfMind

• 

Spoiler :

Before battle commences, there is a RNG roll that determines how many first strike chances will be converted. A common (but wrong) assumption is that each first strike chance has a 50% probability of being converted. Here is how it actually works...

Let #FSG be the number of guaranteed first strikes and #FSC be the number of first strike chances.

Then in battle, the unit will receive #FSG + rand(0,#FSC) first strikes, or equivalently rand(#FSG, #FSG + #FSC) first strikes.

rand(0,#FSC) returns a random number from the uniform distribution (all numbers are equally probable) with lowest value 0 and highest value #FSC. You can basically imagine it as a die with the numbers from 0 up to #FSC on it.

Going back to the 4-7 first strike Drill IV longbow, it would receive:

4 first strikes (25% of the time)
5 first strikes (25% of the time)
6 first strikes (25% of the time)
7 first strikes (25% of the time)

If it were true that each first strike had 50% probability of converting independent of the other first strikes, then the above numbers would have come from what's called a binomial distribution (not the uniform distribution), and they'd have been 4(12.5%),5(37.5%),6(37.5%),7(12.5%).

I didn't know that as well

 

[AcaMetis]

Coinflip odds would have been my guess too, though I decided not to guess. Good thing I didn't .

 

[Plains-Cow]

I will NEVER support Drill promos over Combat promos.