# 2020 Magic: The Gathering Core Set #66

> The 2020 Magic: The Gathering Core Set card Rookie Mistake (#66) is a blue Instant that provides tactical control by buffing one creature while weakening another.

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## Identity

- **Year**: 2020
- **Manufacturer brand**: Magic: The Gathering
- **Set / series**: Core Set
- **Card number**: #66
- **Product type**: TCG_CARD

## Description

Released in 2020 as part of the Magic: The Gathering Core Set (M21), Rookie Mistake is a Common blue Instant card identified by card number 66. Designed by Zoltan Boros, this card serves as a foundational element for players seeking tactical control in limited formats. The card costs a single blue mana to cast, making it an efficient tool for manipulating the battlefield early in the game. In gameplay, Rookie Mistake allows a player to select two target creatures for opposing effects. One creature receives a +0/+2 bonus, enhancing its survivability or combat potential, while a second target suffers a -2/-0 penalty, reducing its power without affecting its toughness. This asymmetrical effect creates strategic depth, allowing players to protect key allies or neutralize threats without removing them from play entirely. The flavor text, "Stop locking your knees as you strike! Now stand up and try again," adds a humorous touch to the card's instructional theme. For collectors, this product represents a staple of the M21 set, reflecting the set's focus on accessible mechanics and clear card design. The card's straightforward text box and common rarity make it a familiar sight in casual play and draft environments. Whether you are building a deck around creature interaction or simply appreciate the strategic utility of the Magic: The Gathering trading card game, Rookie Mistake offers a versatile option.

## FAQ

### What is the mana cost and type of Rookie Mistake?

Rookie Mistake is a Common blue Instant card with a mana cost of {U}. It belongs to the Core Set released in 2020 and is designated as card number 66.

### How does the effect of Rookie Mistake work in a game?

When cast, Rookie Mistake targets two creatures. You choose one creature to get +0/+2 until end of turn, and another creature to get -2/-0 until end of turn. This allows you to boost an ally while weakening an opponent's creature simultaneously.

### Who is the artist for the M21 Rookie Mistake card?

The artwork for Rookie Mistake in the 2020 Core Set was created by Zoltan Boros. The card features the set's standard design language typical of that release.

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Last verified: 2025-11-29.