Barbed Shocker — ruling 1

The number of cards the player draws is equal to the number of cards they discarded, not the amount of damage dealt by Barbed Shocker.

Barbed Shocker : règles, fonctionnement et interactions (MTG)

Barbed Shocker is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Trample, haste Whenever this creature deals damage to a player, that player discards all the cards in their hand, then draws that many cards.

How it works : Barbed Shocker

Original English text — Wizards of the Coast / Scryfall

#1September 25, 2006· Wizards of the Coast
The number of cards the player draws is equal to the number of cards they discarded, not the amount of damage dealt by Barbed Shocker.
No other card is named in this ruling.