Nagoya has standard Magic tournaments almost every day.
-- MONDAY: Card Brunch Kanayama, 6:30
-- TUESDAY: Hobby Station Sasashima, 6:45 pm
-- WEDNESDAY: Hobby Station Mei Eki, 6pm
-- THURSDAY: TCG 193, 7pm
-- FRIDAY: 6pm, FNM, Various locations (check MTG locator), Draft at Big Magic usually if enough people. Prinny Club Kanayama 8pm and 11pm.
-- SATURDAY: Card Labo Mei Eki, 11:30 am - Hobby Station Mei Eki, 2pm.
-- SUNDAY: Big Magic, 11 am. Usually a booster draft after standard tournament (3:30 or later depending on number of participants at the standard event).
There are also Legacy and Modern events held around town during the week.
-- Monday: TCG 193, 7pm (Modern)
-- Tuesday: TCG 193, 7pm (Legacy)
-- Thursday: Advantage Kamimaezu, 7pm (Legacy)
-- Friday: Hobby Station Mei Eki (modern) 6pm, Advantage Kamimaezu (modern and legacy) 6:30pm, TCG Shop 193 (modern), 7pm
-- Saturday: Hobby Station Osu, 1pm (Legacy), TCG 193 (Legacy)
-- Sunday: Hobby Station Osu, 5pm (Modern)
There are also modern, legacy, and vintage events about one time a month at Big Magic as well. Amenity Dream also hosts one Legacy even a month too I think. Check the "Magic the Gathering" tab on the top of my website to get more information about the locations of these stores.