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Hi, I'm trying to piece together a script for the new, unreleased card Etrata, the Silencer. I've gotten it to be unblockable, exile a creature defending player controls when it hits, and put a counter on it (I'm using egg counters as the program had problems with hit counters.) I'm currently stuck on checking the number of creatures in exile with egg counters on them and using the number I get back from that to cause the defending player to lose the game. Any help would be appreciated. I attached the txt file below. Thank you!

(I know it doesn't shuffle itself in yet with my script, I was waiting until I got the loss trigger right for time purposes.)

I think it may be the Card.DefenderOwns - perhaps it should be DefenderCtrl - I cannot see any other script that contains DefenderOwns anywhere, so it may not be an option.