Weight of Conscience — ruling 1

Since the activated ability doesn’t have a tap symbol in its cost, you can tap creatures that haven’t been under your control since your most recent turn began to pay the cost.

Weight of Conscience — ruling 2

The ability exile the enchanted creature, but Weight of Conscience remains on the battlefield. The Aura will then be put into your graveyard as a state-based action.

Weight of Conscience : règles, fonctionnement et interactions (MTG)

Weight of Conscience 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 Enchanted creature can't attack. Tap two untapped creatures you control that share a creature type: Exile enchanted creature.

How it works : Weight of Conscience

Original English text — Wizards of the Coast / Scryfall

#1April 1, 2008· Wizards of the Coast
Since the activated ability doesn’t have a tap symbol in its cost, you can tap creatures that haven’t been under your control since your most recent turn began to pay the cost.
No other card is named in this ruling.
#2April 1, 2008· Wizards of the Coast
The ability exile the enchanted creature, but Weight of Conscience remains on the battlefield. The Aura will then be put into your graveyard as a state-based action.
No other card is named in this ruling.