The ending of The Legend of Spyro: Dawn of the Dragon does this troper in. It's not so much the game that does it. But the fact is she has been a fan of the series since the beginning. Spyro was the initial motivation for her to begin studying animation. So yeah, there's a lot of nostalgia wrapped up in this little purple dude. So after getting through twenty odd hours of infuriatingly difficult gameplay, to then see her favourite character die, (even if it was a Disney Death, we didn't know that until after the credits rolled) and receive a Thank You "for helping us complete this series, without you it wouldn't have happened" to the last decades worth of fans, brought the last ten years of her life back in one big, freaking Tear Jerker of a sob.
Ignitus' story about Cynder's past, if the fact an entire generation of unborn babies was just slaughtered doesn't do it, what was done to Cynder certainly would.
Also, Cynder's explaination at the beginning of The Eternal Night, she's leaving because her past is hurting her so much she can't stand staying somewhere she clearly enjoys being, it's clearly hard for her to leave but she feels she has to. Worse, it's not her fault at all. She's an innocent victim and blames herself for 12 years of murder and destruction she was forced to cause, and is just a poor little kid!
When this troper played ANB, she found herself becoming rather fond of the swamp. Easy game level, pretty lighting, seemed like a rather beautiful place, right? Now consider this: The swamp surrounded the Temple. The Temple that Malefor raised into the sky and turned the land around it into the burned lands. The swamp. And ever wonder what happened to Spyro and Sparx's parents? Hell, this troper was near in tears when she saw the view from the floating isles level, sap that she is. This only made this troper more determined to get to Malefor and make the bastard pay.
Even assuming that their parents survived it, think about this: Spyro and Sparx were last seen in the Well of Souls, which imploded at the same time Malefor was set free. Their parents likely spent the five years between games not knowing there their kids were or if they were still alive.