In fact, decks like Dredge have even used Thoughtseize as an answer to an opponents hate cards

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I see the -3 ability as more of an emergency punch-out than something youll use regularly
You want board states to shift and change repeatedly
Youre using 3 Don to play a 4-cost Character, and two of those Don are used to increase your Leaders attack Power
Elrond of the White Council Elrond of the White Council doesnt have the best execution of secret council