MTR 3.7 New Releases

Newly released card sets become tournament legal for sanctioned, rated tournaments on the following dates:

Hour of Devastation™ July 14, 2017
Ixalan™ September 29, 2017
Rivals of Ixalan™ January 19, 2018

For official Prerelease tournaments only, new sets are legal for use before the official format legal date. In these cases, any announced rules updates shall be in effect at these tournaments, including informal explanations of new rules and mechanics. Judges may apply additional rules that they believe will be updated.

These dates may be subject to change. Any changes will be announced at http://www.magicthegathering.com.