In episode 22 of The Flash, we see

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>  the Arrow (aka Al Sah-him) helping the Flash to capture the Reverse Flash.
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However, the Arrow is currently

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>  pretending to become the next Ra’s al Ghul in the League of Assassins.
>  Oliver mentions that the special arrows used against the Reverse Flash were supplied by Ray Palmer. But Ray is currently held by the League of Assassins, as we see in S3E22 of the Arrow.
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**How was he able to travel to Central City and help the Flash?**