Tuesday, October 10, 2017

How much is having Initiative worth?

So here is an interesting combat question how much initiative is worth to the side having it in various editions of Dungeons and Dragons?

When I was mucking around with Fudge, I wrote a program that simulated two guys whacking the other with swords. I did this to see how the number worked out over thousands of fight. I coded up GURPS Basic Combat and classic DnD Combat to use as comparison.

One of the things I did was randomized starting initiative at the beginning of combat. Then alternated sides from that point on. So I was playing around with it today and I noticed something interesting. When two combatant have equal stats with random starting imitative the odds look like this for 10,000 fights.

Alex Wins 5060
Brian Wins 4940
Average Rds 4.1268

So when I gave Alex starting Initiative all the time. The result was this

Alex Wins 5575
Brian Wins 4425
Average Rds 4.08065
Then switched to Brian

Alex Wins 4512
Brian Wins 5488
Average Rds 4.0986

The implication is that having initiative all the time increases your odds of winning combat by 4.5%. This is especially relevant to DnD 5th edition where the default is to roll initiative once.

Note: Both Alex and Brian had AC 12, +1 to Hit, 1d8 damage, and had 10 hit points.


Scott Anderson said...

Is there a verb missing? :)

Initiative by sides each round. Select action before rolling initiative.


All action simultaneously

Fairest ways to do it

Jerry said...

During our last campaign I ended up trying out different versions of initiative, and then decided to get rid of it entirely; all the PCs go; all the NPCs go; and then any deaths/incapaciations are handled. Which technically means that it is possible for two combatants to kill each other, although in about ten years of that game this happened only once (this involved a magic-user fighting a jaguar alone; the rest of the party got back just in time to administer a healing potion, so the magic-user survived).

Can your program determine how many times Brian and Alex are both defeated in an initiative-less system like that?

FrDave said...

Some of the most memorable moments I have in D&D are initiative rolls. When combat ebbs and flows with round by round initiative, it adds a whole other layer of suspense. I can't count the times my players all had their eyes glued to the die that was coming out of my hand because somebody was depending on initiative to have a chance to survive. Just from a dramatic/entertainment POV I have never understood the desire to only roll initiative once.

Cullen said...

"One of the things I did was randomized starting initiative at the beginning of combat. Then alternated sides from that point on."

I'd be curious to see something modeling the kind of initiative rolled every round--especially because I've seen combats go from "gimme fights" to "oh god! we're dying" in one round after initiatives are rolled for the round, and one side gets a second routine of attacks following the first (and I've had several characters die to this logic, stepping into melee on the hopes of finishing a combat, and then having to suffer through two series of attack routines, which ultimately meant too much damage and then ... death ...)

"Old school" initiative, rolled every round, really made me focus a lot more on the "moment" of combat, rather than just zoning off until my turn finally came around again (twenty minutes later) like I did in Pathfinder type games.

Edgewise said...

I think initiative is going to have more effect when combatants have fewer HP. If you can take out some enemies before they get any chance to attack, that can be huge. Especially if you're also capable of going down to one hit.

Still, I like to give an additional mechanical advantage to initiative. In my homebrew, characters get an initiative bonus equal to DEX modifier plus fighter levels. When an attack is made on an opponent who rolled a higher initiative, it is -2 to hit.

This may sound like a big effect, but it is actually in place of DEX modifiers to AC in my game.

porphyre77 said...

Also, initiative can have way more impact when casting a Sleep spell.

JDsivraj said...

I've been using a rolling round-robinn initiative where a variant of weapon speeds is used for few years now and I've bee happy with the reults.
Each roud each side tolls 1d12 and weapon speeds are considered to determine if individuals are disadvataged in theiir hit chances alog with deciding which side goes first.

It's rolling round robin because which player rolls for innnitiative that round rotates clockwise and their modifiers impact the roll.Having clumsy or lucky allies in a fight can swing the tide of batttle.

JDsivraj said...

(Oops sorry double reply I hit the button too soonn)

I ran a bunch of simulated fights with the two sample guys and found if you always let one fighter go first that fighter wo 55 to 58% of the time. Alternating with fighter A going first on odd rounds and fighter B going first on even rounds still gave fighter A the win 52 to 56% of the fights.
Strictly random initiative each round and the odds were effectively 50%.

Unknown said...

Two guys, one on one, wailing on each other with melee weapons does not accurately model the combat variability of, say, a party of 5 PCs of different classes fighting against 3 goblins and 4 wolves.

Combat takes long enough as is (looking at you, player who isn’t prepared for their turn!) - why make it take longer for a false sense of “realism”? The only justification I can think of: if everyone at the table thinks the variant initiative is really more fun.

Robert Conley said...

@DM Dave, the fact the circumstance of a combat encounter varies doesn't change the fact that with all other factor being equal that having the initiative is an advantage. I attempted to to figure how much of an advantage it was.

I don't need to have a more complex situation to get a rough measurement. Because no matter how complex the encounter is in order to isolate how effective initiative you have to replay it the same way each time only varying who goes first. To do otherwise means you are introducing other factors that increase or decrease the odds of winning.

Unknown said...

@Rob Conley -- I do agree with what you have presented. Initiative is a variable that gives the high rolling side/individuals an edge, especially in an evenly matched battle. I do appreciate the efforts you put forth to demonstrate this!

My point is more directed at the commenters that presume this is a flaw in the game and so seek to "fix" initiative. Many variables contribute to giving one side or the other the upper hand in an encounter: "winning" initiative and striking first, having more spell slots available than your opponent, being fully healed prior to the encounter, simply being lucky with the attack and damage dice, etc, etc. IMHO, "fixing" one thing is unlikely to have a significant positive effect on outcomes - just be careful of those house rules that could have the unintended consequence of making game play slower, unbalanced, and/or less fun.