Am I missing something? I can't seem to see in the rules how initiative can be affected when trying to set up an ambush.

I am guessing that advantages on a stealth roll might add to boost dice for the initiative roll. 1 Advantage adds a boost to your own initiative, 2 advantages to another player, triumph for the whole party.

Are there RAW for this?

"The base difficulty for an initiative check is Simple"

So this allows you as GM can set higher difficulties if the situation warrants it, situational factors can also add Setback. So in a well placed ambush the attacker could be getting a couple of Boost, meanwhile the targets of the ambush have an Average Difficulty with a Setback.

I choose to define the moment that the ambush is sprung as the start of the first round of combat. If the one setting the ambush gets top spot then they succeed in springing their trap. If the targets of the ambush get top spot then something gives away the game and at least 1 target gets to dive for cover.

I don't think there is anything about ambushes in the Core book, except for the initiative stuff; Cool or Vigilance, that kind of thing.

When I run ambushes, I have the ambushers roll Stealth opposed by the ambushees Perception. Success means the ambush goes ahead; any uncancelled success/advantage gets added to the ambushers initiative score when they roll their Cool check. Triumphs get a surprise round. If they fail the Stealth check, it is initiative as normal.

1 hour ago, Andreievitch said:

Am I missing something? I can't seem to see in the rules how initiative can be affected when trying to set up an ambush.

I am guessing that advantages on a stealth roll might add to boost dice for the initiative roll. 1 Advantage adds a boost to your own initiative, 2 advantages to another player, triumph for the whole party.

Are there RAW for this?

No. I just have whatever party is being ambushed roll initiative with an appropriate Difficulty.

I think I like my idea I will run with that.

I assume you're already using Cool for the characters setting the ambush and Vigilance for the characters being ambushed?

1 hour ago, Richardbuxton said:

I assume you're already using Cool for the characters setting the ambush and Vigilance for the characters being ambushed?

Of course! That is the core mechanic, but I think they should use successes/adv/triumphs from the prior Stealth (hiding) roll to the following Initiative roll, rather than getting a free attack. I would like to see better mechanics behind that.

I was surprised not to see that kind of thing in the Soldiers book, perhaps it's coming in the Spy book.

I definitely agree the character setting the trap should make some rolls to determine how effective the trap is. The results should definitely impact the Initiative, but I think there are benefits to the first actions too that can carry over. Such things could be Cover, Aiming, perhaps ignoring environmental Setback for a round.

1 hour ago, Richardbuxton said:

I was surprised not to see that kind of thing in the Soldiers book, perhaps it's coming in the Spy book.

I definitely agree the character setting the trap should make some rolls to determine how effective the trap is. The results should definitely impact the Initiative, but I think there are benefits to the first actions too that can carry over. Such things could be Cover, Aiming, perhaps ignoring environmental Setback for a round.

Agreed. I am going to run with the PCs choosing any skill they want to use to help set up the ambush. Stealth, Know - Warfare, maybe even Acrobatics to perch up in a branch. Then let them use the roll results to boos init, add to cover, aim etc.

All this only adds to the narrative setting

The system is super easy to modify, hence I don't feel that these details should need to be covered in suppliment books as anything more then an aside; offering an option on how to play rather then providing an update.

Whatever you do decide though, once the initiative is rolled the players should be aware of what is going on. It can be frustrating to have a GM ask for an initiative roll and then when you go first you're expected to pretend like nothing is happening. If nothing is happening, why did I roll initiative?

Everyone's turn occurs at the same time initiative means that your maneuvers and actiona get the benefit of taking effect at a particular time during this shared period. So if you win initiative and someone is attacking you, you are aware of this attack prior to your opponenta attack and can react accordingly, if you land your hit first this does not mean that you attacked first, just that its effects are felt first.

Also, you can always describe the enemy sniper missing their first shot, or you noticing a laser dot on your ally, etc. Something that clearly initiates combat as a story but doesn't have a mechanical effect dependent on the turn order.

I always run lowest NPC group stealth vs vigilance of the most vigilant PC (or the other way around), to determine if the ambush takes them by surprise. Successes give the ambushed party difficulty for the initiative roll (every 2s give 1d) and triumph and advantage give either boost die or upgrades, like in the RAW. Setback the same, as well as despair.

8 hours ago, TheMOELANDER said:

I always run lowest NPC group stealth vs vigilance of the most vigilant PC (or the other way around), to determine if the ambush takes them by surprise. Successes give the ambushed party difficulty for the initiative roll (every 2s give 1d) and triumph and advantage give either boost die or upgrades, like in the RAW. Setback the same, as well as despair.

Why lowest/highest and not a group check? It seems like that's exactly what group checks should be used for.

17 hours ago, TheMOELANDER said:

I always run lowest NPC group stealth vs vigilance of the most vigilant PC (or the other way around), to determine if the ambush takes them by surprise. Successes give the ambushed party difficulty for the initiative roll (every 2s give 1d) and triumph and advantage give either boost die or upgrades, like in the RAW. Setback the same, as well as despair.

Why two rolls at all? Why not have the surprisee's Initiative opposed by the surprisers relevant skill (e.g. Stealth, Deception) straightaway?

2 hours ago, Grimmerling said:

Why two rolls at all? Why not have the surprisee's Initiative opposed by the surprisers relevant skill (e.g. Stealth, Deception) straightaway?

That takes a lot away from the Cool skill, though. Ambushing someone is exactly what that skill is for.

Why does everyone assume you need to use Stealth when you Ambush? 300m away on a rooftop in the middle of a busy city you could be doing jumping jacks wearing a T-shirt that says F the Emperor and no one will notice you before you open fire. Crowded streets with lots of people all over but no one looking any different in particular, the shooter isn't hidden, they're right there, until the gun fire starts, though the PCs are oblivious prior, maybe, depends on how good their Vigilance is. I'm not saying Stealth can't be used at times, but it isn't required in every instance and that's why it's better to just stick with Cool I think.

Advantages.and successes on a roll to set up the ambush should certainly improve your initiative roll. Perhaps successes upgrade and advantages add boost. Failures upgrade difficulty threat add setback. Easy enough

Some scenarios warrant an extra check, not all. Doesn't always have to be a stealth check. I have an encounter written and prepared where I will be using Deception for the ambush check; the attackers are all dressed as workers in an otherwise innocuous environment. The party are going to be faced with a Deception check, I plan to add the uncancelled successes (as described above) to enemy initiative. I've been trying to concoct other ways of using different Skill checks in order to surprise my PCs.

For most encounters, and ambushes, cool/vigilance is fine, but I like adding in an extra skill check sometimes can help add a bit of narrative spice to an otherwise mundane scenario. I mean most combat is one side trying to get the jump on the other, which is why Cool and Vigilance works so well. That standard d20+modifier for initiative in other systems seems arbitrary as everyone just tries to find the most janky way to boost up that modifier. Having those two opposing skills makes initiative much more dynamic and fun.

I agree that it should only apply to specific encounter, hence why it hasn't come up in my game before.

This occasion is an ambush the PCs will have to set up. It is actually the ambush from Takeover at Whisper Base from the AoR Beginner box. I am modifying the game to fit my campaign.

In the game they sneak into the Imperial base and then hear troopers approaching. They have just enough time to set up a quick ambush. The game suggests the PCs can use Stealth, Deception, Athletics etc. It is the result of these rolls that I would like them to add to their initiative rolls if they choose.

18 hours ago, Stan Fresh said:

That takes a lot away from the Cool skill, though. Ambushing someone is exactly what that skill is for.

So? Where's the problem? The ambusher's Initiative roll would stay Cool (Simple). The only difference is that the ambushed's Vigilance check would be opposed by the appropriate skill - often Stealth, but possibly Cool, or Survival, or Charm, or Deception, or Education, or whatever the situation is calling for.

Example for Vigilance (vs. Cool):