So for a while now I've been mulling over a mechanic wherein you have cards that serve a dual purpose. Each card can either be held in your hand to be used as an action or left in play after playing them as an action to gain a passive benefit from them. The idea being you choose between keeping your options open and having increased flexibility or having all around more powerful, but fewer, options due to the passive benefits from leaving cards in play.
Are there any games that explore this type of mechanic that I can look at for inspiration? Can you think of a type of game that this mechanic would fit in well? Any advice for designing a game around this sort of mechanic?
Interesting. I'm curious to see more of your game and how it implements and iterates on this!
Though I am talking a little more specifically than just dual function cards as I think is the case in your later two examples, so perhaps I should respond with an example of my own to clarify.
Lets say you have three Actions you can take each turn, represented by cards. You have three cards that can be played to gain either 3 meat, 3 vegetables, or 3 bread depending on the card. At the end of the turn, after collecting your foodstuffs, you can choose to leave the Action card in play and, if you do, it gives you one of the corresponding resource at the start of each of your turns, but in exchange you can't choose it from your hand to play it to get the three resources. (Though at the end of any turn you can return any number of cards in front of you back to your hand.)