What they're summoning depends on the ritual, which we don't have the details of. We'd have to get that from the leaders, somehow. But given that they don't worship any one deity in particular, it seems that way.

They want their wishes granted, at any cost. They believe they will summon a god capable of doing this. Whether or not it's true, when your lives mean nothing to them, it's an easy cost to pay.

[They say this all in a generally staid voice, polite but not warm.]