As Ahmet and Andrej climb the stairs, the dwarves reorganize themselves. Palt climbs to the top of the pyramid, and Warth clears the bottom of the stairs for freer movement. None of the dwarves are able to attack this round (only Lukas and Ahmet were able to see any kobalds).
The kobalds will fight back.
The bowmen all reload. Those two on the yellow level will be moving back up the stairs. The kobald swordsmen will rush forward.
Palt will be attacked by one kobald, who succeeds in hitting him for 2 damage. Palt is not stunned.
Ahmet finds himself surrounded by 8 kobald attackers:
The two in 3008 and 3109 both gain a +1 bonus for flanking him. Ahmet is missed by them, then hit by the kobald in 3208 in the orange and brown jersey, and takes 3 damage. Then Ahmet proceeds to have a bad day: he's hit by both kobalds in 3107, and the right kobald in 3209 scores a natural 20 for double damage. He takes, in order, 2 damage, then 4 damage, then 6 damage ... I think the last one might have stunned him (if Ahmet has 24 hit points or less after taking the first three of four hits. I have it that Ahmet has taken 29 damage since the start of this.
Ahmet being stunned, he is driven back down the stairs, bypassed by Andrej and more or less caught by Warth, all the way down to 2909. Two kobalds do move into the hex at 3108, so Andrej will have to attack from his place on the stairs.
The kobalds finish their attack and the party can move.