# 2020 Magic: The Gathering Core Set 2021 #66

> Rookie Mistake is a Common Instant card from the Core Set 2021 set, identified by set code M21 and card number 66. The card has a mana cost of {U}, a mana value of 1, and colors of U. It features a normal layout and is illustrated by Zoltan Boros.

Canonical URL: https://supercatch.com/product/magic-the-gathering-core-set-2021-rookie-mistake-66

## Identity

- **Year**: 2020
- **Brand**: Magic: The Gathering
- **Set**: Core Set 2021
- **Card Number**: 66
- **Featured**: Rookie Mistake
- **Game**: Magic: The Gathering
- **Rarity**: Common
- **Mana cost**: {U}
- **Type**: Instant
- **Color**: U
- **Language**: English
- **Material**: Card Stock
- **Finish**: Normal

## Description

Rookie Mistake is a Magic: The Gathering trading card game card. It is an Instant with a mana cost of {U} and a mana value of 1. The card belongs to the Core Set 2021 set (M21) and holds a Common rarity. It is card number 66 in the set, features a normal layout, and is illustrated by Zoltan Boros.

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Editorial content updated: 2026-10-11.

Site deployment: 2025-11-29.