"Have you felt it Lord Sombra? There has been an awakening. I will finish what you started. I will silence Harmony once and for all. The light, will be no more."

Sombra's horn is still out there somewhere in the snow. Its just a matter of time before somepony finds it. Evil never truly dies. It merely waits for the right moment to return…

In regards to Sombra's horn not being surrounded by Flurry's magic field, I couldn't get it to look quite right. Let's just say that the horn is absorbing her magic, rendering the aura invisible. A tainted thing like that would almost certainly have some strange properties to it.

Vectors used:

Just the horn
The chest was given to Flurry as a birthday present, since it was no longer needed to hold the Elements of Harmony
Evil Flurry