The Flash season 3 will premiere Tuesday October 4th at 8pm on The CW, Arrow season 5 will premiere in the same timeslot on Wednesday October 5th, Supergirl season 2 on Monday October 10th, and Legends of Tomorrow season 2 on Thursday October 13th.
The promo also gives us glimpses of some new characters, including Kid Flash, who starred in the latest season 3 trailer for The Flash.
Starting on October 4 with season 3 episodes of The Flash, the Arrowverse now officially includes Supergirl, which formerly resided in an alternate reality on a different network.
It includes characters from long-running series like Supernatural, entering its 12th year, all the way to brand new series like Frequency.