Reproducibility:
I had 'Pulling the strings', 'Corruption of the soul', 'Revealing the secret', 'Desolation of the heart' and 'Weapon Dance'.
I played 'Weapon Dance' + chained 'Pulling the strings', which asked me to select corruptions to be attached. I have selected 2 of them from my hand: 'Corruption of the soul' and 'Desolation of the heart'.

Recap:

Description:
After selecting 2 corruptions I was not asked to select opponent hero, but the game said smth like: "Wrong selection of cards." I clicked "OK", and the same meassage reappeared again. And it was reappearing after each "OK" click. I had to quit the browser (Firefox).

Setup:

Screenshots:

require you to select a corruption out on the field to one of the characters, cards in your hand are considered inactive and therefore are the wrong cards like the message told you.

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Ty Boadicea for the awesome farewell gift. Now just to think up an avatar to go with it. Anyway, I'm still a Sap/Nomad/Pirates fan and user.

So maybe the game interface should not allow me to select corruptions from my hand.

Eh, I attempted recreate your bug and no matter what I did I couldn't select the corruptions in my hand.

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Ty Boadicea for the awesome farewell gift. Now just to think up an avatar to go with it. Anyway, I'm still a Sap/Nomad/Pirates fan and user.