Mirrodin is orbited by four satellites, which are called suns and moons interchangeably, that correspond to red, black, white and blue magic.

The set focuses on five main regions on Mirrodin, each corresponding to a part of the Magic color pie: The main character of the story is the elf Glissa Sunseeker, who visits all these places, guided by revenge against the machines that killed her family.

In the story, Glissa, Bosh, and Slobad journey deep within Mirrodin's core to confront the insidious Memnarch.

As rage and despair overcome her, Glissa's body calls forth a great column of green mana from Mirrodin's core, annihilating the avatar in the process.

Mirrodin is notable for being the first expansion set to feature the new card front design (which debuted in 8th Edition).

The problem prompted Wizards of the Coast to change the bordering background of artifact cards to a much darker grey in Fifth Dawn.

Thus the number of cards released each year would stay the same, but then Magic developer Randy Buehler explained that Wizards believed this change would make it easier for collectors and players to keep up with the number of new cards as these would be released more homogeneously over the course of the year.

Fifth Dawn theme decks contained a few reprints from Mirrodin and Darksteel with the improved card face.

The artifact subtype Equipment, which has become a staple of Magic, represented weapons, clothing and armor that could be wielded or worn by creatures.

Darksteel continued the Equipment, Affinity, Imprint and Entwine mechanics, and introduced the indestructible and modular keywords.

These enhanced the power of cards with the "Affinity" mechanic by increasing the number of artifacts in play while still being considered lands.

Notable cards in Fifth Dawn include Crucible of Worlds, Engineered Explosives, Serum Visions and Vedalken Shackles.