is it random from feeding them, or do I have to do something special?

random. Last time I did this years ago it was about 1 in 70. They change what they ask for every five minutes. If you buy scratchcards, you can use this as timer and wait until they ask for something you have already.

Alright, thanks for the help! Here's hoping a cute little autumn dragon will follow me.

you are welcome and good luck!