Emerl is a robot made of heartwarming. He calls Amy "Mom," is on good terms with the entire cast, and even tries to be nice to Eggman.
For most of Sonic Battle, Shadow is bent on destroying Emerl, with Sonic protecting the robot (who he had befriended) being his main obstacle. Then during the second to last story, to Shadow's surprise, Sonic simply lets him take Emerl with him a few moments after he (Shadow) reaffirmed that he was going to destroy the robot. It then turns that after seeing how similar he and Emerl are, Shadow sympathizes with him and chooses to help him rather than destroy him. Sonic had seen all of this development coming and had Emerl go with Shadow to make it happen.
Shadow's episode features him willingly relinquishing his Chaos Emerald—the only one that hasn't been absorbed by Emerl—in order to awaken Emerl and complete his evolution as the Gizoid. When Rouge expresses concern over this, Shadow merely replies, "It's okay. I have Maria in my heart." Given all of the horrors Shadow has had to endure, coupled with his own self-loathing in Battle over his status as a bioweapon, the fact that even one of the darkest, most jaded and brooding characters in Sonic mythos recognizes that true power comes from the bonds one makes in life with their loved ones is a Heartwarming Moment in and of itself.
As flanderized as Amy is in this game, she still cares deeply for Emerl, and he calls her "Mom" in return.
Emerl refusing to fight Eggman's robots because he doesn't want to make Cream sad.
Shadow thanking Rouge for saving him.
Sonic telling Shadow that he and Emerl both have hearts, and wouldn't willingly kill anyone.
Rouge telling Shadow and Emerl how to free Emerl's mind from his programming.
Emerl thanking everyone at the end of Shadow's chapter, saying that when he was with Sonic and friends, despite their fighting he didn't feel worried. He felt fun, excitement, and happiness.