Here's a clip coming from the final minutes of Kamen Rider Wizard's 50th episode. After Koyomi gives Haruto his Infinity Ring, it's time for his final showdown with Fueki aka the White Wizard.
As you can see at the near end of the episode, we learned that Koyomi is the Philosopher's Stone and the Gremlin Phantom just rips it out from her body, causing her body to deteriorate. The bigger question is can Haruto find a way to revive her?