Episode 20, "Soul of the Guardian"
*****SPOILERS*****
Synopsis: Both of the guardians end up being like Alphonse, armors with souls attached via alchemy, and formerly condemned prisoners. They both do battle with their opponents. While Alphonse has little trouble with his opponent, who identifies himself as Barry the Chopper, Edward struggles against his. He eventually beheads the warrior, but his victory is short lived, because there in another soul in the body of the armor. The other one attacks and Ed is forced to use deconstruction to disable him. Unsuccessful in a physical fight with Alphonse, Barry uses psychological tactics, suggesting Alphonse is a fake, his memories all false ones his brother created. Alphonse reels from this, as Edward refuses to finish his enemies, since he considers his brother human, and thus them.