A powerful combination of methods makes this a versatile tool for birthday divinations. You can always carry this set of 4 cards in your wallet. Any participant's exact birthday (date and month) can be divined using any of the dozen combo methods built into the cards. The range of different methods enables one to repeat this for different participants in the same group. Apart from the exact birthday, other information like zodiac sign, ruling planet etc about the participant can also be revealed. There is nothing to reset and the cards are fully examinable before, during and after the performance. The cards can also be used as 'hidden in plain sight' cribs for propless version.
For some of the methods, just a little bit of memory will be required, but there are options to work around that too. The set of 4 cards look mysteriously beautiful and you will enjoy using them.