The counters to a played Silencer are (from best to worst):
Destruction
-Bark Convoy in field.
-Goblin Fireworker in field.
-Herald of Despair in field.
-Gnome Power Engineer in a Path to trascendance. / Herald of Despair in a Path to trascendance.
-Bark Convoy in a Path to trascendance.
-Goblin Fireworker in a Path to trascendance.
-Merchant of Souls bringing back Gnome? I need to test this.
Resource mitigation
-Reincarnation Spirit in the graveyard.
-Reverence (Ne'eva heropower).
-Any 5 mana card like Pegasus Regiment or Pandemonium.
-Reincarnation Spirit in hand.
-Any 3+ cost spell with Thamic Reflector in play.
-Any 2- cost spell with Thamic Reflector in play.
I believe I am forgetting something :/