# 2021 Magic: The Gathering Magic Online Promos #89990

> The 2021 Magic Online Promos card Devastating Mastery (#89990) is a six-mana-value white sorcery featuring an alternative cost mechanic and board-wiping effects.

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## Identity

- **Year**: 2021
- **Brand**: Magic: The Gathering
- **Set**: Magic Online Promos
- **Card Number**: 89990
- **Featured**: Devastating Mastery
- **Game**: Magic: The Gathering
- **Rarity**: Rare
- **Mana cost**: {2}{W}{W}{W}{W}
- **Type**: Sorcery
- **Color**: W
- **Language**: English
- **Material**: Card Stock
- **Finish**: Normal

## Description

Devastating Mastery is a rare sorcery card from the 2021 Magic Online Promos set, identified by card number 89990. Illustrated by Jake Murray, this white card requires a mana cost of {2}{W}{W}{W}{W} with a total mana value of six. The card introduces a strategic alternative payment option: players may choose to pay {2}{W}{W} instead of the full mana cost. When this reduced cost is paid, the card triggers a specific interaction where an opponent must select up to two nonland permanents they control and return them to their owner's hand. Regardless of the cost paid, the card's primary effect destroys all nonland permanents on the battlefield. This design creates a high-impact moment in the game, offering a decisive board state change for the caster. This 2021 Magic Online Promo card, Devastating Mastery, is a Rare Sorcery with a mana cost of {2}{W}{W}{W}{W}. The card belongs to the white color identity and functions as a standard sorcery within the game's rules. Its placement in the Magic Online Promos subset makes it a distinct item for completists and players interested in digital-to-physical crossover releases.

## FAQ

### What is the mana cost of Devastating Mastery?

The mana cost for Devastating Mastery is {2}{W}{W}{W}{W}, resulting in a mana value of six. Players have the option to pay an alternative cost of {2}{W}{W} if they choose.

### What set is Devastating Mastery from?

This card is from the Magic Online Promos set, released in 2021. It carries the card number 89990 and is classified as a rare promo card.

### What does Devastating Mastery do?

As a sorcery, Devastating Mastery destroys all nonland permanents. If the alternative cost of {2}{W}{W} was paid, an opponent also chooses up to two nonland permanents they control and returns them to their owner's hand.

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Editorial content updated: 2026-10-10.

Site deployment: 2025-11-29.