On the Wave Rider, Martin Stein & Jackson found something very unusual, a secret cabinet which Captain Rip Hunter has been hiding from the entire team. They discovered an elaborate techno-lab filled with heavy weaponry and an audio message from Barry Allen in the year 2056. He is saying to Captain Hunter that he couldn’t endanger any more lives and that he must not reveal this piece of information to his team. The Firestorm at first decided not to tell about the secret hatch and message to the rest of the team. Later, in the CW-Crossover event, they told the Flash about the secret message that his future version sent to Hunter but it’s still a mystery why he did it.
There is now a strong possibility that Barry may be having critical information about Legion of Doom whose two members – Reverse Flash and Captain Cold are familiar to Barry, they may be responsible for mass casualties in the future and he is giving a heads up to Captain Hunter. Well, now he is back but he has been reprogrammed with a new identity by the Legion. He doesn’t remember anything about his past. The larger question is – Why has he come back? You need to know just three words – Spear of Destiny.
In the mid-season finale, Sara traded the mystical amulet with Reverse Flash for the life of Prof. Stein. He discovered that the powers of the talisman may be beyond anyone’s imagination, he talked about “spear of destiny”, a powerful artifact (reality gem) that can be used to reshape time & space with a fine comb. What is the one thing that Reverse Flash wants to accomplish in his life? He wants to get rid of Barry Allen without erasing himself in the timeline. Well, now he has the ultimate weapon to literally alter the reality.