Recently I played with a player which had a flamethrower that shoots green flames. The only item I know about that is able to apply such green flames is the Spectral Flame spell from the Halloween event.
Screenshot from SleightSoda.
I used this spell on my flamethrower at this Halloween event but it has been removed after the event ended. Oddly enough this spell is still in some inventories but the description says:
This item will expire on Wednesday, November 12, 2014 (8:00:00) GMT.
My question now is:
Which item do I need to get these green flames? Is the item with expire date the correct one?