# 2021 Magic: The Gathering Magic Online Promos #89990

> The 2021 Magic Online Promos foil release of Devastating Mastery, a rare white sorcery featuring a unique alternative mana cost.

Canonical URL: https://supercatch.com/product/magic-the-gathering-magic-online-promos-devastating-mastery-89990-foil-promo

## 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**: Foil

## Description

Devastating Mastery is a rare sorcery card from the 2021 Magic Online Promos set, identified by card number 89990. This white mana spell features an alternative cost structure that allows players to pay {2}{W}{W} instead of its full mana cost of {2}{W}{W}{W}{W}. When this reduced cost is utilized, the card forces an opponent to return up to two nonland permanents to their owner's hand, and subsequently destroys all nonland permanents on the battlefield. The card was illustrated by Jake Murray. This Magic Online Promo card is a foil Rare sorcery from the 2021 set. The foil finish adds a distinct visual quality to the card, distinguishing it from non-promotional base set prints. The gameplay mechanics of Devastating Mastery make it a powerful board-clearing tool within the game's framework. Its ability to potentially wipe the entire board while also removing specific permanents makes it a notable inclusion for players who build decks around white mana strategies. The card's rarity designation further emphasizes its limited distribution during its initial release period. The card features a mana cost of {2}{W}{W}{W}{W} and allows you to pay {2}{W}{W} instead to return up to two nonland permanents to their owner's hand, or destroy all nonland permanents. The combination of its unique rules text, foil treatment, and promotional status creates a distinct catalog entry for enthusiasts of the trading card game.

## FAQ

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

The card has a mana cost of {2}{W}{W}{W}{W}, but it features an alternative cost allowing players to pay {2}{W}{W} instead.

### What effect does Devastating Mastery have?

It returns up to two nonland permanents an opponent controls to their hand and then destroys all nonland permanents.

### Which set does Devastating Mastery belong to?

It is part of the Magic Online Promos set, released in 2021, and carries the card number 89990.

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Editorial content updated: 2026-10-03.

Site deployment: 2025-11-29.