Amy Rose is a hedgehog that wields an infinite count of Piko Piko Hammers.
Willaca's fanverse (Sonic Y)
In the Sonic Y continuity, Amy is Will's beloved younger sister and an Assassin at training. Amy also has a hatred for Sonic as she thinks Sonic treats her "like dirt" but doesn't choose to go against him. Because she knows he is good at heart and believes that she shouldn't fight Sonic (even though she does at times) . Amy also has adopted Ashura from an orphanage. She is also alot more mature and sounds more mature.
Meeting Mecha Topaz
Mecha Topaz attacks Amy and almost kills Amy in Sonicpower Comics Issue 6. The attack was getting a gunshot through her body. Amy was left in critical condition, with Mecha Topaz winning the battle against everybody in New Mobotropolis (including Knuckles, NICOLE, Mina, Tiara, Honey and etc.) and of course, destroyed the city.