---
name: "Professor Onyx"
mana_cost: "{4}{B}{B}"
cmc: 6
type_line: "Legendary Planeswalker — Liliana"
colors: ["B"]
color_identity: ["B"]
keywords: ["Magecraft"]
set: "STX"
set_name: "Strixhaven: School of Mages"
collector_number: "83"
rarity: "mythic"
artist: "Kieran Yanner"
oracle_id: "9df2e909-ed13-456a-9636-7398732009a9"
canonical_url: "https://avascry.com/printing/professor-onyx-stx"
legalities:
  commander: "legal"
  standard: "not_legal"
  modern: "legal"
  pioneer: "legal"
  legacy: "legal"
  vintage: "legal"
  pauper: "not_legal"
  penny: "not_legal"
---

# Professor Onyx
- **Mana Cost:** `{4}{B}{B}` (CMC: 6)
- **Type:** Legendary Planeswalker — Liliana
- **Starting Loyalty:** 5
- **Keywords:** Magecraft

## Oracle Text
Magecraft — Whenever you cast or copy an instant or sorcery spell, each opponent loses 2 life and you gain 2 life.
+1: You lose 1 life. Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
−3: Each opponent sacrifices a creature with the greatest power among creatures that player controls.
−8: Each opponent may discard a card. If they don't, they lose 3 life. Repeat this process six more times.

## Top 4096-Dim Neural Synergies
1. [Liliana, Death Mage](/printing/liliana-death-mage-plst.md) — Legendary Planeswalker — Liliana
2. [Sorin, Grim Nemesis](/printing/sorin-grim-nemesis-sir.md) — Legendary Planeswalker — Sorin
3. [Liliana of the Veil](/printing/liliana-of-the-veil-pdmu.md) — Legendary Planeswalker — Liliana
4. [Liliana, Waker of the Dead](/printing/liliana-waker-of-the-dead-pm21.md) — Legendary Planeswalker — Liliana
5. [Sorin Markov](/printing/sorin-markov-plst.md) — Legendary Planeswalker — Sorin
6. [Nicol Bolas, the Deceiver](/printing/nicol-bolas-the-deceiver-hou.md) — Legendary Planeswalker — Bolas

## Printing Details
- **Set:** Strixhaven: School of Mages (STX) #83
- **Rarity:** Mythic
- **Artist:** Kieran Yanner
- **Total Printings:** 31 across all historical editions

## Format Legalities
Commander: `legal` | Standard: `not_legal` | Modern: `legal` | Pioneer: `legal` | Legacy: `legal` | Vintage: `legal` | Pauper: `not_legal` | Penny: `not_legal`