Blaze: How to animate reactively when some field in the database change

Lets say there is a deck of four cards.
When I click on one, the mongo field ‘bestAlternative’ gets the index of this card.

  1. How would I then reactively kick off an animation to flip the card.
  2. I can ‘page’ to a new set of cards and the selected one should flip automatically

I’m using Shape from Semantic UI for card rendering and animation, but the details are not important to me. My problem is more of a conceptual nature. I’ve read about Template.x.onRendered/ rendered but infact my cards never get rendered even I ‘page’ to a new set and their content changes. The update function of Blaze seems too tight, so only the attributes of the cards get updated but not the card itself. The only solution I see is to make templates out of these attributes, and wait for onRendered, but then I would need to do this for every changing attribute. Not a good idea.

Could you describe point per point how you would approach such a problem?
Thank you