Cheapest priced copy (Tempest): $2.29 at Card Kingdom, near mint, their price list as of .
Shocker 
Creature — Insect · 1/1 · Rare · Tempest · #204
Whenever this creature deals damage to a player, that player discards all the cards in their hand, then draws that many cards.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper