Daethwin sighed, but stretched a little as everyone else prepared too. Walking over to the edge of the hole, he eyed it with distaste. Rather than entering, he reached into his pack and pulled out a small viola, sitting cross-legged in front of the hole, though ready to bolt at a moment's notice. He tuned it swiftly; an advantage of being so very musically inclined as he was meant that he could do so within a few seconds, considering that almost any bard worth half a coin had perfect pitch, and this one was no exception. A hundred songs running through his head, the bard mused over his options.
Considering the creatures before him, he picked out a few and began to play. The music, as it began to echo through the chamber, harmonizing with itself even before he opened his mouth and began to sing. weaving them into a starkly contrasting melody that combined funereal dirge with songs more fit to be heard at a summer festival. The first part, he played to the servitors. Calming, soothing, relaxing...songs to bring them closer to their final rest, the peace that awaits those who have been pulled from their blessed relief in the afterlife when they have finally been put down. Perhaps it might convince a few of them to stave off their attack, long enough to gain an advantage and let them fall to their deserved peace. He hoped it was deserved, anyway.
The other half of the song, he wrapped around his, errr...'friend', Thales. The angelkin would almost certainly have a connection to light in the first place, so he should make a good conduit through to the physical world, as his sword, face, and body in general began to glow brightly with a golden light. The sunlight would bloom outwards from the angelkin, not obstructing him, nor blinding Daethwin's allies, but giving illumination and, hopefully, subduing or destroying the undead creatures they had to fight now.
Even with all this going on, he still managed to try and keep something prepared to counter and disrupt anything the servitors might cast; it was unlikely they could all cast spells, but if they were as powerful as they looked, it was far from impossible.