New art project - HELP needed

So I've been "hired" to start working on playing cards and do altered art. It's sooooo much work. If there is anyone out there who know what pen/markers to use on cards that won't smudge (cuz sharpies have failed) please let me know. I do most of them with paint, but I'm trying ink (since that is more of my forte).

Please help me! :S