# 2017 Magic: The Gathering Magic Online Promos #62989

> The 2017 Magic Online Promos release featuring Yahenni's Expertise, a foil rare sorcery designed by Jason A. Engle for competitive Magic: The Gathering gameplay.

Canonical URL: https://supercatch.com/product/magic-the-gathering-magic-online-promos-yahennis-expertise-62989-foil

## Identity

- **Year**: 2017
- **Manufacturer brand**: Magic: The Gathering
- **Set / series**: Magic Online Promos
- **Card number**: #62989
- **Product type**: TCG_CARD

## Description

Designed by artist Jason A. Engle, this black mana card costs {2}{B}{B} and provides a significant tactical advantage by reducing all creature power and toughness by 3/-3 until end of turn. Beyond clearing the battlefield, the card allows you to cast a spell with mana value 3 or less from your hand for free, enabling powerful combo lines and value generation. Whether you are building a themed collection or seeking specific promotional pieces for your library, this card represents a key moment in the game's evolving design landscape.

## FAQ

### What is the mana cost of Yahenni's Expertise?

Yahenni's Expertise has a mana cost of {2}{B}{B}, totaling four mana. It is a single-color black sorcery that requires three black mana sources in your deck to cast.

### What does Yahenni's Expertise do in gameplay?

This sorcery deals two effects: it gives all creatures -3/-3 until end of turn, and you may cast a target spell with mana value 3 or less from your hand without paying its mana cost. This makes it a versatile tool for board control and resource advantage.

### Who is the artist for the Magic Online Promos version of this card?

The foil rare version of Yahenni's Expertise from the 2017 Magic Online Promos set was illustrated by Jason A. Engle. His artwork complements the card's dark, arcane theme typical of black mana spells.

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Last verified: 2025-11-29.