It's not a bug, it's just how the game works now. Well, depending upon the type of player you are, you may or may not believe this to be a bug.
When you enchant a player, their weapon gets fire damage, ok? If that weapon also has a property of firing explosive arrows (i.e., Raven Claw, Demon Machine, Kuko Shlockakoo) then the fire damage is transferred to the explosion as well.
A person wearing a Raven Claw at level 15, therefore, can do the kind of damage that my characters were doing when properly enchanted. And that damage reached almost 4700 fire damage. So when you fire an exploding arrow, everything in the range of the explosion will receive the damage shown in your LCS. LCS being the Lying Character Screen, because it's never 100% accurate.
Dueling with enchant is considered very poor form, and in HC you have to look for people who are 'chanted. Anyone carrying a Raven Claw (and they do not reflect the "hot" color when enchanted so you have to know what you are looking at) has about a 99.9% chance of being enchanted.
At the end of last season I went dueling with enchant only because I was bored. Cheap ears, cheap ears. One hit kills all over the place.