The burn blood effect is not reduced by effects that reduce the cost of the card (eg. Adana de Sforza).
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Selective Silence
Only usable during the first round of combat.
Maneuver.
Only usable before range is determined. Burn 1 blood to set the range for this round.
Rulings
The card cannot be played if the minion cannot afford to burn the blood.
Once the range is set, no other effect can be used to reset the range that round, but other pre-range effects can be played afterwards. Skip the Determine Range step for that round.
If another effect was already setting that round's range (e.g. Neutral Guard), that effect has priority.