This is not true, as damage is tracked individually, and all of this damage must be dealt by the same commander
Teysa works better with some cards than others and being a touch on the luxury / win-more side of things you do have to be a little careful with her
The second is Grma Wormtongue, which seems specifically designed to counter Soul Sisters decks and turn off lifegain
However, some of them have useful abilities that make this unfortunate drawback worth working around, and one of these strategic options is Cradily
Cyrus Conspiracy is also great to search for things like power spray (to prevent uxie), scoop up (for Blaziken, Crobat, or Chatot) energy gain for Blaziken, energy for blaziken, supporters like another Cyrus Conspiracy or Cyrus Initiative to disrupt your opponents hand further
The card is highly prized for completing the Aqua versus Magma rivalry