We can use the checkbox field for the same purpose! All you need is to create a required checkbox with no available option! 

@genietim, while waiting for a reply, could you care to elaborate on how you can *conditionally* prevent a card from being moved by setting it to “required” and showing/hiding it using conditionals? 

i am not quite sure I understand how you do that, but I would love to get an insight on what you were doing. My experience with conditionals has been frustrating so far. Thanks and regards!

@Grafeno ; I already have my response, Juliana’s answer is perfect.

But to answer your question: the general setup is this:

• you can use conditionals to show/hide fields based on other field’s values
• cards cannot be moved while required fields are not filled in BUT only if those required fields are also visible (i.e. not hidden using conditionals)
• therefore, the approach is to have a field that cannot possibly be filled in (e.g. the case seen above: a checkbox without a checkbox). While it is shown, the card cannot be moved. If you hide it with the conditionals, the card can be moved.