# 2020 Magic: The Gathering Core Set #278

> The 2020 Magic: The Gathering Core Set foil mythic rare Rin and Seri, Inseparable. This legendary creature bridges canine and feline mechanics with powerful synergies.

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## Identity

- **Year**: 2020
- **Manufacturer brand**: Magic: The Gathering
- **Set / series**: Core Set
- **Card number**: #278
- **Product type**: TCG_CARD

## Description

Card number 278 in the set, this mythic rare features the unique subtypes Dog and Cat, allowing it to interact with both factions simultaneously. In gameplay, Rin and Seri serves as a versatile engine. Whenever you cast a Dog spell, you create a 1/1 green Cat creature token. Conversely, casting a Cat spell generates a 1/1 white Dog creature token. This bidirectional benefit encourages deck builders to mix tribal strategies, creating a self-sustaining board presence. Additionally, the card possesses an activated ability that requires one red, one green, and one white mana, plus tapping the creature. This effect allows you to deal damage to any target equal to the number of Dogs you control, while gaining life equal to the number of Cats you control. This dual impact makes it a formidable threat that rewards careful resource management. Collectors value this print for its foil finish and mythic rarity, which denote its status as one of the most sought-after cards in the M21 expansion. As a key piece for completing the core set, it represents a significant milestone for enthusiasts of the Magic: The Gathering trading card game. Whether you are building a tribal deck or expanding your collection of legendary creatures, this card offers both mechanical depth and aesthetic appeal.

## FAQ

### What are the card types for Rin and Seri, Inseparable?

Rin and Seri, Inseparable is a Legendary Creature with the subtypes Dog and Cat. This dual classification allows it to trigger abilities associated with both tribes simultaneously.

### How does the ability of Rin and Seri, Inseparable work?

The card creates a 1/1 green Cat token when you cast a Dog spell, and a 1/1 white Dog token when you cast a Cat spell. Its activated ability deals damage equal to your Dog count and gains life equal to your Cat count.

### What is the mana cost for this card?

The mana cost for Rin and Seri, Inseparable is one generic mana, one red mana, one green mana, and one white mana. It has a mana value of 4.

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Last verified: 2025-11-29.