Lower level priests and blood sacrifices.

[Ygorl]

Well, Jade Knives aren't that hard to forge, nor are more powerful priests all that hard to hire.
It is true that they're not as good at it as they used to be, but they used to be *really* good. A crappy priest with a jade knife is still three times as effective as a normal temple...

[Endoperez]

Of course, temples are more expensive. 500 gold? Or 400? Something like that.

[Daynarr]

400 temples, 500 labs.