It won't come as a huge surprise when I say combat has been joined. What I did in the rolling thread was roll the goblins' Dexterity (Stealth) and compare it to everyone's passive perception scores: That's 11 for Kovoir, and 13 for Pieron and Zuzie. Pieron, being vigilant and suspicious going in, additionally had advantage. On active checks, this means rolling twice and taking the better; on passive scores, this translates to a +5, for 18, but the goblins rolled high enough to beat him anyway.
The goblin ambushers achieve surprise against everyone, meaning only they can act in the first round of combat. Had they beaten Kovoir and Zuzie but not Pieron, say, Pieron would have gotten to act too.
Two goblins jump out to attack Pieron in melee; one misses, the other hits and deals 5 damage. I've decided to use the average damage provided in all monster statblocks in 5e here so that I can tell you 5e gives that option, so that I don't have to make two posts for every attack, and because I'd rather kill you because you did something stupid than because I rolled maximum damage at level one.
A third goblin is hiding behind the bushes and shoots at Kovoir and Zuzie, but misses.
Roll initiative. Initiative is a straight up dexterity check, no proficiency bonus or anything. The initiative order is as follows (I will put this at the top in future spoiler blocks):
Goblin Reaver 14 - AC 15, HP 7
Goblin Reaver 4 - AC 15, HP 7
Goblin Archer 3 - AC 13, HP 7
Here's how combat basically works: You're assumed to be able to ready your weapon at the start of combat without having to spend an action to do it or anything, unless there's a pressing reason you can't. In a fight, you have one action each turn, and can additionally move up to your speed. You can take your action at any point during your movement. In addition, some things are done as a bonus action, such as Pieron's rage. This means an action you can take in addition to your normal action, but you can only take one bonus action per turn. They're essentially swift actions from 3rd edition with a different name.
Finally, here's an encounter map. Note that one square is ten feet, rather than five, hence the strangely sized tokens. I've taken the liberty of making tokens; if you'd like different art, let me know, making a new one is trivial. I've cropped the full map for convenience and filesize; north is up.
(http://i.imgur.com/CZMJZch.png)