What is the plane of existence in MicroProse's 1997 "Magic the Gathering"?

In MicroProse's 1997 Magic: The Gathering, the plane of existence is Shandalar. This is because the game is set in the world of Shandalar, where players can explore the vast landscapes, encounter various magical creatures, and engage in battles with other planeswalkers while collecting spells and artifacts. Shandalar provides the backdrop for the game's storyline and gameplay mechanics, making it the central plane of existence in this iteration of the popular card game.