A watchlist is the list of cards you are hunting: the binder gaps, the grails, the maybe pile. Cards can sit on several lists at once, added straight from any card page.
Sharing
Lists are private by default. Make one public and it appears on your profile for anyone to follow; invite specific collectors and you build a list together. A group hunting a master set can work from one shared list.
Alerts
Set a threshold on a card and we watch the market for you: above a price, below a price, on the version and grade you choose. When it crosses, you hear about it. Free accounts run three active alerts; Pro runs unlimited.
Watchlists feed the rest of the platform too: the prices browser can filter to watched cards, so a reprice sweep of your hunt list is one click.