223 Styx Master of Shadows please ! <| sep |> Rip doesn ' t give a fuck , he wants to save his family . Also not everything is solidified . Time doesn ' t care how you get there but It ' s got set events . Flashpoint ? Barry ' s method allows him to see immediate changes . Though really it ' s because he ' s going back a decade at most . As we saw in legends , they say what could become the new timeline all through season 1 . But because it all happened many decades ago and causes such a big ripple , it takes a while . Barry saving his mom is relatively close enough and impact a small amount of the world . So he see ' s the immediate changes . For all we know the ripples were still going . The problem with the cement is this . The ripples can wipe you out . As Stein is experiencing , it may be hard to change anything if you can remember the original timelineor you know if you even exist .