# 2021 Magic: The Gathering Strixhaven: School of Mages Promos #83s

> The Professor Onyx foil promo card from Magic: The Gathering's 2021 Strixhaven set, featuring the legendary planeswalker Liliana in her mythic rare foil treatment.

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## Identity

- **Year**: 2021
- **Manufacturer brand**: Magic: The Gathering
- **Set / series**: Strixhaven: School of Mages Promos
- **Card number**: #83s
- **Product type**: TCG_CARD

## Description

Released in 2021 as part of the Strixhaven: School of Mages Promos set, this Professor Onyx card is a notable entry for Magic: The Gathering collectors. Identified by card number 83s and the PSTX set code, the card features the legendary planeswalker Liliana in a distinctive foil finish.

Collectors often seek out this promo card to complete their Strixhaven collections or to add a powerful, visually striking planeswalker to their library. The foil treatment enhances the card's aesthetic appeal, making it a desirable item for both competitive players and casual enthusiasts. Its status as a promo card from the Strixhaven era adds to its historical value within the Magic: The Gathering universe. Whether you are looking to expand your collection of Liliana cards or acquire a high-rarity foil from this beloved set, this Professor Onyx card represents a significant piece of TCG history.

## FAQ

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

Magecraft triggers whenever you cast or copy an instant or sorcery spell, causing each opponent to lose 2 life and you to gain 2 life. This ability makes the card particularly effective in decks that focus on casting multiple spells per turn.

### Is Professor Onyx a legendary planeswalker?

Yes, Professor Onyx is a legendary planeswalker card featuring the character Liliana. As a mythic rare card from the Strixhaven: School of Mages Promos set, it is one of the highest rarity tiers available in Magic: The Gathering.

### What does the '83s' card number indicate?

The '83s' designation identifies this foil promo card within the Strixhaven: School of Mages Promos subset. This unique identifier helps collectors track and organize their collections of promotional cards released alongside the main set.

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Last verified: 2025-11-29.