A resident in costume presents the dressing in a subway car for the annual Halloween Skytrain party in Vancouver, Canada, Oct. 26, 2018. Hundreds of people dressed in costumes take a ride with the Skytrain - Vancouver's public rail transit system to enjoy the annual Halloween themed flash mob party. (Xinhua/Liang Sen)

Costumed participants take a train ride during the annual Halloween Skytrain party in Vancouver, Canada, Oct. 26, 2018. Hundreds of people dressed in costumes take a ride with the Skytrain - Vancouver's public rail transit system to enjoy the annual Halloween themed flash mob party. (Xinhua/Liang Sen)

A resident in costume presents the dressing at the subway platform for the annual Halloween Skytrain party in Vancouver, Canada, Oct. 26, 2018. Hundreds of people dressed in costumes take a ride with the Skytrain - Vancouver's public rail transit system to enjoy the annual Halloween themed flash mob party. (Xinhua/Liang Sen)

A resident in costume presents the dressing in a subway car for the annual Halloween Skytrain party in Vancouver, Canada, Oct. 26, 2018. Hundreds of people dressed in costumes take a ride with the Skytrain - Vancouver's public rail transit system to enjoy the annual Halloween themed flash mob party. (Xinhua/Liang Sen)

A resident in costume presents the dressing in a subway car for the annual Halloween Skytrain party in Vancouver, Canada, Oct. 26, 2018. Hundreds of people dressed in costumes take a ride with the Skytrain - Vancouver's public rail transit system to enjoy the annual Halloween themed flash mob party. (Xinhua/Liang Sen)

Costumed participants take a train ride during the annual Halloween Skytrain party in Vancouver, Canada, Oct. 26, 2018. Hundreds of people dressed in costumes take a ride with the Skytrain - Vancouver's public rail transit system to enjoy the annual Halloween themed flash mob party. (Xinhua/Liang Sen)

A resident in costume presents the dressing at the subway platform for the annual Halloween Skytrain party in Vancouver, Canada, Oct. 26, 2018. Hundreds of people dressed in costumes take a ride with the Skytrain - Vancouver's public rail transit system to enjoy the annual Halloween themed flash mob party. (Xinhua/Liang Sen)