# 2021 Magic: The Gathering Magic Online Promos #90088

> This 2021 Magic Online Promos release features Professor Onyx, a foil mythic rare Liliana planeswalker card designed by Kieran Yanner.

Canonical URL: https://supercatch.com/product/magic-the-gathering-magic-online-promos-professor-onyx-90088-foil-mythic-rare

## Identity

- **Year**: 2021
- **Manufacturer brand**: Magic: The Gathering
- **Set / series**: Magic Online Promos
- **Card number**: #90088
- **Product type**: TCG_CARD

## Description

The 2021 Magic Online Promos release of Professor Onyx stands as a distinct foil mythic rare card within the Magic: The Gathering universe. Designed by artist Kieran Yanner, this card number 90088 features the legendary planeswalker Liliana, bringing her signature dark magic to the tabletop. Collectors of Magic Online Promos cards often seek this print for its high rarity tier and the iconic character it portrays.

As a mythic rare, Professor Onyx commands attention in any collection. The foil finish adds a layer of visual depth that distinguishes it from non-foil versions, making it a prized addition for enthusiasts of the Magic: The Gathering trading card game. The card introduces the Magecraft ability, which triggers whenever a player casts or copies an instant or sorcery spell. This mechanic allows each opponent to lose 2 life while the controller gains 2 life, creating a dynamic advantage in gameplay. This life-gain effect is central to the card’s identity, reflecting Liliana’s manipulative and powerful nature.

The card’s abilities extend beyond Magecraft. Its +1 loyalty ability allows the controller to look at the top three cards of their library, put one into their hand, and place the rest into their graveyard. This card selection provides strategic depth, helping players manage their resources effectively. The -3 ability forces each opponent to sacrifice a creature with the greatest power, showcasing Liliana’s dominance over the battlefield. Her ultimate ability, the -8 loyalty effect, challenges opponents to discard cards or suffer life loss, repeated multiple times for devastating impact.

For collectors of Magic: The Gathering, this Professor Onyx card represents more than just a game piece; it is a testament to the creativity and depth of the Magic Online Promos set. The combination of its mythic rarity, foil treatment, and powerful gameplay mechanics makes it a standout item for any serious collector. Whether you are building a deck around Liliana or simply appreciate the art and design of high-rarity cards, this release offers significant value. The card’s design and mechanics reflect the intricate world-building that Magic: The Gathering is known for, ensuring its place in the hearts of players and collectors alike.

## FAQ

### What is the Magecraft ability on Professor Onyx?

Magecraft is a triggered ability that activates whenever you cast or copy an instant or sorcery spell. When it triggers, each opponent loses 2 life and you gain 2 life, providing a significant life-total advantage.

### Who is the artist for the 2021 Professor Onyx promo card?

The 2021 Magic Online Promos Professor Onyx card was illustrated by Kieran Yanner.

### What are the primary abilities of the Professor Onyx card?

Professor Onyx features several powerful abilities. Her +1 loyalty lets you look at the top three cards of your library, put one into your hand, and exile the rest. Her -3 ability forces opponents to sacrifice their largest creature, while her -8 ability challenges opponents to discard cards or lose life.

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Last verified: 2025-11-29.