Soul Ransom — ruling 1

In most cases, you'll enchant a creature controlled by an opponent, which will cause you to gain control of that creature. Any of your opponents can activate the last ability of Soul Ransom by discarding two cards. When that ability resolves, you'll sacrifice Soul Ransom and draw two cards.

Soul Ransom — ruling 2

You'll draw two cards even if you can't sacrifice Soul Ransom, perhaps because it left the battlefield in response to Soul Ransom's ability.

Soul Ransom : règles, fonctionnement et interactions (MTG)

Soul Ransom 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

Enchant creature You control enchanted creature. Discard two cards: This Aura's controller sacrifices it, then draws two cards. Only your opponents may activate this ability.

How it works : Soul Ransom

Original English text — Wizards of the Coast / Scryfall

#1March 14, 2017· Wizards of the Coast
In most cases, you'll enchant a creature controlled by an opponent, which will cause you to gain control of that creature. Any of your opponents can activate the last ability of Soul Ransom by discarding two cards. When that ability resolves, you'll sacrifice Soul Ransom and draw two cards.
No other card is named in this ruling.
#2March 14, 2017· Wizards of the Coast
You'll draw two cards even if you can't sacrifice Soul Ransom, perhaps because it left the battlefield in response to Soul Ransom's ability.
No other card is named in this ruling.