"Pure Talk" Upgrades Basic Cards To "Destroy," But Doesn't Work Right

I had a few situations with the card "Pure Talk," in which it could upgrade basic starting cards like "Fast Talk" to their upgrades with the "Destroy" keyword, but after I played the "Destroy" copy of "Fast Talk" when its upgraded from "Pure Talk," the basic card is still in my deck after the encounter ends (but it stills destroys itself in the battle). I thought the "Fast Talk" is supposed to no longer be in my deck after the encounter if its upgrades to the "Destroy" side through "Pure Talk." Here's a picture of the card in questions that applies that effect.