First let’s start at the beginning with Oliver Queen aka The Green Arrow

Source: http://www.movieweb.com
Second, we have Sara Lance AKA Black Canary

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But lets not forget that Laurel Lance takes over her sister’s role when Sara is killed by Oliver’s sister.

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Next comes Roy Harper or better known as Arsenal.

Source: http://www.hypable.com
Meanwhile, in Central City, a freak accident turns Barry Allen into The Flash.

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The freak accident also creates Firestorm

Source: http://www.cinemablend.com
Then in comes Ray Palmer aka ATOM

Source: nerdist.com