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I'm trying the new Atraxa, Praetors' Voice and I've read in several places that the Experience Counters in cards such as Meren of Clan Nel Toth and Ezuri, Claw of Progress are valid targets for the Proliferate Mechanic. I've tried to select both of them when the proliferate triggers and I'm not able.

Can it be done?

Exp Counters are placed on the Player, not on the Card (like Energy or Poison)

I did not notice that since I play mostly on mobile and it's kinda hard to see
Oh man, going downhill and without breaks....
Thanks a lot!