Historical Rules · 27 April 2018
Rule 408.3
Official source text from the 27 April 2018 Rules release
In the Planechase, Vanguard, Commander, Archenemy, and Conspiracy Draft casual variants, nontraditional Magic cards and/or specially designated cards start the game in the command zone. Each variant has its own rules regarding such cards. See section 9, “Casual Variants.”