The easy way to copy a card is using the filmstrip. To do this, follow these steps:
Right click on the card you want to copy and choose Copy. (You can also use Cmd/Ctrl-C to copy).
You can then select multiple cards using shift and copy them all at once, or select them all using Cmd/Ctrl-A.
Lastly, open the new gamma and hit Cmd/Ctrl-V to paste.
