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

> Professor Onyx is a Legendary Planeswalker — Liliana card from the Strixhaven: School of Mages Promos set (code: PSTX). This Mythic Rare promo card features a Foil finish and was illustrated by Kieran Yanner. It has a mana cost of {4}{B}{B}, a mana value of 6, and colors of B. The card has a loyalty of 5 and a normal layout.

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## Identity

- **Year**: 2021
- **Brand**: Magic: The Gathering
- **Set**: Strixhaven: School of Mages Promos
- **Card Number**: 83s
- **Featured**: Professor Onyx
- **Game**: Magic: The Gathering
- **Rarity**: Mythic Rare
- **Mana cost**: {4}{B}{B}
- **Type**: Legendary Planeswalker — Liliana
- **Loyalty**: 5
- **Color**: B
- **Language**: English
- **Material**: Card Stock
- **Finish**: Foil

## Description

Professor Onyx is a Magic: The Gathering trading card game card. It is a Legendary Planeswalker — Liliana with a mana cost of {4}{B}{B} and a mana value of 6. The card is colored B with a color identity of B. It has a loyalty of 5 and a normal layout. This card is part of the Strixhaven: School of Mages Promos set (set code: PSTX) and is identified as a promo. It is a Mythic Rare card with a Foil finish. The artist is Kieran Yanner. The card number is 83s.

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Editorial content updated: 2026-10-11.

Site deployment: 2025-11-29.