You dont need credit card or anything, just download, make account and start playing!!!!
It is kinda like diablo based system
It is not as good as other MMRPGS like lineage, DAoC,etc but its good enough
Only bad thing i see is that you cannot cuztomized your character look so much =( and it looks kinda kiddy game
I don't like Priston Tale myself, there's nothing to help you out in the beginning, nothing to tell you what to do, you just go until you see something and hit it, and it's usually a bunny or a blob or a mushroom.