Barry Allen takes a turn for the worse in Flash #41, all according to Grodd's plan, while both Wallys take pains to fix what their mentor can't.
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Luis Guerrero
The Flash #52 deals with both the Speed Force and the Strength Force, and is helped along greatly by Christian Duce's artwork.
The Flash #45 is a nice break between major story arcs, but it's not lacking in either heart or hype. The long-awaited reunion between Iris and Wally brings not only tears of joy, but also important revelations that set up Flash War. nicely.
The Flash #57 wraps up the Rogues and Renegades arc while dealing with the Sage Force, and displays surprising sensitivity towards Mick while doing so.
The Flash #46 explores Wally's fragmented memories and how their return affects his own emotions as well as Barry's, while still setting the scene for Hunter Zolomon's ultimate revenge.