Mad Prophet — ruling 1

Discarding a card is part of the ability’s activation cost. You can’t activate the ability if you have no cards in hand.

Mad Prophet : règles, fonctionnement et interactions (MTG)

Mad Prophet 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

Haste , Discard a card: Draw a card.

How it works : Mad Prophet

Original English text — Wizards of the Coast / Scryfall

#1May 1, 2012· Wizards of the Coast
Discarding a card is part of the ability’s activation cost. You can’t activate the ability if you have no cards in hand.
No other card is named in this ruling.