Rosie says to Milo, "Well, I appreciate the kind words. I mean it's only right to offer any insight I can if your intention is to stop these people. No one deserves a slave's life."

If anyone intends to climb up the ship with the grappling hook, please indicate where you're climbing from and make a STR Athetics check (DC 11). Remember there are sentries walking up and down the length of the ship on both sides in alternating directions and 1 is near the mast.

The bombs are simple to operate, just a standard fuse and you can easily light them with a flint and blade, which all of you would have

After watching the sentries go by, she's hoping to have had a fair judge of their timings. When she's ready, she'd be aiming for the stern at a timing after the sentry had already turned his back on the area and was a fair distance away. Flipping her hood over her head, Ban takes her grappling hook, twirls it around a few rotations, and tosses the grappling hook up to the deck siding. Testing of its sufficiently attached, by way of a couple cautious tugs, she makes a good leap up. If there's an angle to get to the top from the position started, that's alright. With her second storywork training (Thief archetype), scaling vertical obstacles can sometimes be just a good way to get from point a to point b. 

Athletics check: 20

If/when she's nearing the top of the ship, Ban will slow down, be quieter, and be listening for the sentry's approach. When the timing seems right, with him a fair start to the longer portion of his route down the ship, she'll haul herself over and go from there.

Ban successfully makes her way up to the stern deck. The sound of the splashing wake hitting the hull conceals the sound you make while climbing the rope. When you get to the deck, you see the 3 sentries on the boat, as well as 3 on the dock. None of them seem to notice you.

The sentry on the starboard side (where you are) is making his way to the bow and is roughly 20 ft away and moving away from you. The glow of his torch moves away with him. You can detect the faint smell of alcohol in the air behind him. The sentry on the port side does not see you and is near the bow, but making his way back to the stern, where you are. His torch illuminating the area around him. You're currently safe where you are, but the port sentry may see you when he gets to the stern.

Is anyone else coming aboard with Ban?

If not, go ahead and proceed with the rest of your plan. If you row away from the boat again, please make stealth checks to avoid being noticed.

Milo is the second one who needs to go up on the ship.he knows climbing isn't his strong suit, but he tries to do his best and imitates Ban.

Athletic: 11

It's not easy and Milo struggles his way up but manages to get next to Ban. He looks at her and just gestures to ask her where to place the bomb.

Milo you just barely make it aboard, your leg gets stuck on the rail and you nearly fall into the water, but you manage to pull yourself aboard. You and Ban are in the same spot on the ship. If you intend to move around on the deck then make Stealth checks (remember advantage from darkness).

Grol and Xander, you both see them climb aboard without issue and appear to remain undetected.

Grol smiles seeing his friends making the deck of then ship. He turns to Xander and whispers, “You have an energy about you, friend. You seem... conflicted. What part of the world do you come from?”

Motioning for Milo to follow, Ban looks to the nearest cover and rushes forward. If possible, staying close to larger objects and netting. If even more possible, to get to a cabin wall and start on a trajectory inside the ship. 

Stealth: 22

Ban, you hide behind a couple barrels and boxes then dart below deck. There appears to be a few sleeping sailors in bunks, but they don't wake up and there is a strong smell of alcohol. There are rows of benches on each side with a few dozen sets of shackles anchored to them.

Milo, you see Ban hide then see her dart out of site as she goes down a staircase leading below the main deck.

Grol, Xander, Og, and Rosie see a torch held by a humanoid figure pacing back and forth. You also hear sporadic chit chat by a couple of them. It has been about 1 minute since Ban and Milo climbed aboard.

Seeing Ban and Milo climb up successfully Xander concerned about their safety must push on. He knows Ban can get them out of trouble if it comes to it. Hearing Grol "I used to live closer to the capital my uncle you see is a court wizard... Og, let's move towards the northern stream like Rosie suggested. Stay low people..."

Stealth: 9 or 12

"O'tay, Og row now." He says then begins rowing towards the North side of the island

Stealth 14

Need stealth from Grol as well (with advantage)

Grol Stealth: 14 

Milo sees Ban moving quietly on the ship and shows him to follow. He'll take a deep breath and try to follow quietly. 

Stealth: 18

The lifeboat manages to sneak by the dock and boat sentries unnoticed and are navigating their way to the North side of the island. As you make your way closer to the clearing, you see a shallow brook flowing into the ocean and the area is moderately forested with tropical trees. You make out the faint glow of campfires off in the distance being reflected off the trees further inland.

Milo, just before waiting for the opportune moment to follow Ban, you see the lifeboat rowing away, presumably towards the North side of the island. You and Ban are down below and you also notice the sleeping sailors and rows of benches with dozens of shackles anchored to them. You both hear the sound of creaking footsteps from the sentries on the top deck and snoring of the passes out drunken sailors.

Rosie says to Xander and Grol, "We should be momentarily out immediate danger of being spotted, but we definitely need to be alert when we make landfall."

Xander will cast Message to Ban about 120ft out. "We are going ahead to the northern side of the isle, once you and Milo get the bomb plant just take their life boat and row like hell... Don't die."

Ban makes her way downwards, looking for where their powder kegs are stored. Making certain that her movements are silent and looking for anything of concern. All the while, she'll glance back to check on Milo. I sure hope he is as quiet as he is small. Though, if he gets caught, he'll probably be able to just talk them to death. With an internal chuckle, Xander's voice is heard. 

"Hey Xan, I'll try and get some means of transit, but it might come down to swimming. We'll catch up with you up North. Die? Not quiet yet, I'm sure; far too young."

Looking and smiling over her shoulder to Milo, she gives her best 'let's go' look and keeps on.

Ban and Milo, you make your way to the bottom deck, their meager supplies of powder kegs look adequate enough to blow the ship apart. Their ship is not maintained very well and is not supplied very well. You see nothing obvious of value to acquire.

As Ban and Milo are looking for a place to plant the bombs, you both hear above deck with your passive perceptions:

"Oi! ... Yeah, go ahead and bring the supplies on board! ... Nope, not a damn thing going on here! ... Aye mate! ... All thanks to the city of Black Root!"

It sounds as if he's yelling to someone probably either on the dock or close to it. The footsteps on the top deck sound faster then you both hear "Alright, alright damn it. I'll go make room down below."

You hear a single set of footsteps approaching from the top deck on the stairs headed down below...

"Aw, ****!" With a head tilt towards the nearest cover, perhaps behind some barrels or whichever looks best, Ban takes to hiding. 

To hide: 9

When Milo hears the sounds of the steps approaching, he also tries to hide behind a barrel or something he can find. 

Stealth: 18

The sentry comes downstairs below deck looks around for a moment, sighs, and begins moving cargo around. His back is currently turned to both of you. It looks like he's going to be down here a while. He is a human dressed in leather armor with two shortswords on each hip. The sound of wood and sand grinding fills below deck as you both remain hidden.

Grol, Xander, both of you continue rowing and are approaching the North side. Looking back to the ship you can see at least 6 torch lights moving from the glow of the main camp towards the ship Ban and Milo boarded.

Grol turns toward Xander. “You think they need a distraction?”