There's no card called "Card Guard" in the Yu-Gi-Oh! anime or in the official card game. It's possible you're thinking of a different card, or a custom card created by a fan.
Could you provide more information about this card? Maybe:
* A description of the card's effect?
* The anime series where you saw it?
* Any other details you remember?
With more information, I can help you find out what you're looking for!