Butler automation when a custom field is "not yet set"

[Angie]

I am trying to set up automation that will add a sticker to a card if a custom field with a drop-down is not set at all. I see how to add automation if the field is set to a certain value, and I can add automation if the value is cleared. But I do not see a way to add automation when a field has not yet been touched either way. In other words, when a card is created with that custom field, it would automatically show a sticker until that field is set one way or another.

Alternatively, I would like to set a field as "required" or "mandatory" so that it cannot be created without some value being set. I do not see a way to do this either.

Thanks for any help.

[Ludo · Accepted solution]

Hi

You can try rules like this 

when a card without custom fields "MyField" completed is added to the board, add the red label to the card

 When you are adding card trigger you can add too inclusion or exclusion commands concerning custom fields or other datas (filter icon is present into card trigger)

Concerning mandatory fields see this

https://community.atlassian.com/t5/Trello-questions/Mandatory-Fields/qaq-p/1275854

[Angie]

Thank you for this suggestion! Let me try it out!

[Angie]

This is exactly what I needed - I appreciate the help!