What you were expecting to happen, and what actually happened?
Dracos 1337 doesn’t drain mana from an enemy. This is happinig all the time.
What are the steps to make it happen again?
It just doesn’t drain mana.
Do you have any screenshots or video you want to share with us so we can see the problem? Attach them to your post!
Drain =/= Steal
Simply put, DRACOS 1337 does not acquire the mana drained.
If you mean that even once the silence has ended that the inflicted troop still has their mana intact, the pictures really don’t do this justice.
Thank you for quick replay, you are right on point. I don’t know why i assumed that he will steal mana and not just drain it. Maybe I had a mirage at first couple of battles with this troup 
Thank you again!