Elf spawn

Elves did spawn at the faster rate on the three days of Xmas, which helped build up an initial surplus (provided you could play on those days, of course). After that they reverted to the current slower rate. (But the slow rate is still sufficient to get all the prizes, if you're patient, and if you're not too badly affected by server issues.)

It's been mentioned in another thread that they might soon be offering some premium purchase to increase elf spawn rates though.