Svartalfheim

((Apologies, meant to announce I was disappearing for a couple days, but yes, Ludo's next plan of action is going to be to play and use the spell lullaby, followed by the spell sleep the following round, so I'll wait till others decide their plans and then I'll post that action))

Upon reaching their position Arlette looks through the hole to assess the situation and let Kull know what to expect on the other side.

She turns to Kull "Climb or smash?" she asks quietly, her crossbow in hand with a bolt loaded ready to cover him as best she can.

Kull grabs the ram with a grin and responds: Smash. Lend me a hand and im sure we will break that wall down in no time.
He grabs the ram and takes a step backwards before ramming it with all the force he can muster against the weakend part of the wall.
(strength check without ram bonus)1d20+5
(a ram gives a +2 for the strengh check) (if Arlette helps he gets a +2 on the strength check at least i read it that way feel free to correct)

DM what roll do I need to do to help Kull?

Kull gets a +2 because he's using a ram. Arlette if you help him, he gets an additional +2, you don't need to roll to help.

Guys, Kull and Arlette are about to smash open the wall. I assume this will be after Ludo plays his song. Girgory and Kai, for now, I'll assume that as soon as Ludo is done, you guys will rush in while Kull smashes down the wall?

DM that's what I was thinking about doing.

As they move up the wall, Ludo keeps his head down and cradles over the fiddle, keeping it out of harms way - he'd rather take the arrow to himself than damage the fiddle. Despite feeling like a long time as the arrows reign down, in only a matter of moments the small group are up against the wall and it's Ludo's time to shine.

He draws his fiddle and begins to play a soft tune, as he does so, he concentrates and allows the magic to flow through the notes.
He casts Lullaby
(TARGET: Living creatures within a 10-ft.-radius burst; EFFECT: Makes subject drowsy; -5 on Spot and Listen checks, -2 on Will saves against sleep. [SR:Yes; DC:12, Will negates]

As he continues to play, Ludo begins to move into a decresendo moment in the piece, he allows different magic to slow through the notes, and Ludo begins to cast Sleep
(TARGET: One or more living creatures within a 10-ft.-radius burst; EFFECT: Puts 4 HD of creatures into magical slumber. [SR:Yes; DC:13, Will negates])

HD = d6
4d6

Ludo, you don't need to roll Hit Dice, the spell works by just targetting up to 4 HD (targetting lowest level dice first, then closest). Because you're not taking damage I would say that there's no need for a Concentration Check to cast the spells. The DC for Lullaby is 12, the DC for Sleep is 13.

13 Will Saves against Lullaby.

It's easy to see that most of the bandits begin to stagger and rub their eyes.

After you move onto casting sleep, the closest 4 bandits try to stay awake.

Three of the bandits immediately fall asleep. Most of the remainder are sleepy and are having trouble staying awake, at least for a few moments.

Order of battle is now whoever posts first, followed by the sleepy bandits.