---
name: "Professor's Warning"
mana_cost: "{B}"
cmc: 1
type_line: "Instant"
colors: ["B"]
color_identity: ["B"]
keywords: []
set: "STX"
set_name: "Strixhaven: School of Mages"
collector_number: "84"
rarity: "common"
artist: "Kieran Yanner"
oracle_id: "e3c8e552-d315-486d-a176-813b3a300174"
canonical_url: "https://avascry.com/printing/professors-warning-stx"
legalities:
  commander: "legal"
  standard: "not_legal"
  modern: "legal"
  pioneer: "legal"
  legacy: "legal"
  vintage: "legal"
  pauper: "legal"
  penny: "not_legal"
---

# Professor's Warning
- **Mana Cost:** `{B}` (CMC: 1)
- **Type:** Instant

## Oracle Text
Choose one —
• Put a +1/+1 counter on target creature.
• Target creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

> *オニキス教授は双子に、闇の魔道士エクスタスに備えるよう促した。その様子は、暴君の出現に関する詳しい事情を知っているかのようだった。*

## Top 4096-Dim Neural Synergies
1. [Masterful Flourish](/printing/masterful-flourish-sos.md) — Instant
2. [Oblivion's Hunger](/printing/oblivions-hunger-znr.md) — Instant
3. [Unlikely Aid](/printing/unlikely-aid-anb.md) — Instant
4. [Take Up the Shield](/printing/take-up-the-shield-msh.md) — Instant
5. [Armor of Shadows](/printing/armor-of-shadows-hbg.md) — Instant
6. [Mortal's Resolve](/printing/mortals-resolve-bng.md) — Instant

## Printing Details
- **Set:** Strixhaven: School of Mages (STX) #84
- **Rarity:** Common
- **Artist:** Kieran Yanner
- **Total Printings:** 11 across all historical editions

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