Courage readies her axe and drops down out of the tunnel. As she steps out of the way to allow the others to enter, the ants notice her and attack immediately.
** Round 1 **
17 Shaimon Hu'u: is stuck in a tunnel
15 Courage Bloodstone: burries her axe into an ant as it charges (17+2+7=hit, 1d8+1=8 damage)
12 Jonas Cleighton: is stuck in a tunnel behind Tanith Dathius
12 Tanith Dathius: is stuck in a tunnel behind Shaimon Hu'u
6 Dyspeer: growls and barks, but is stuck in a tunnel behind Jonas Cleighton
4 Giant ants: charge and attack courage (19+2+1=hit, 2d4+3=11 damage; 6+2+1=miss; 15+2+1=hit, 2d4+3=6 damage)
** end of round 1 **
[sblock]Dropping out of the tunnel and making a 5-foot step will count as a move action, and you can come out one at a time, one PC per round. While you're in the tunnel waiting for your turn to exit, you can still ready anything that needs readying, including spells. The tunnel is narrow enough that you can brace yourself against the walls to free your hands if you need to (for casting and whatnot).
Assuming the melee stays near to the tunnel opening from which you are dropping (which it is now), you should be able to make a single attack as well.
I hope that's clear enough; this is kind of a confusing situation. At least for me it is.

[/sblock]