I think some people are missing the point of why this particular enemy is unique. Finding one with a flaming sword is the unique part of this enemy. The enemy model is easy to find and is in a lot of dungeons. This type is not. He is more difficult because he sets the oil (?) on fire when he swings the weapon. He may look like an enemy everyone has seen but this variant is unique.
Also, the guys who found this have a group where their sole purpose is to find unique enemies/level variants/etc. in the randomized versions of the chalice dungeons. The group is called the Tomb Prospectors. They have found a lot of fun things, including unique wandering bosses, unique enemies (outside of this guy), and unique dungeon formations.
On another note, I find the chalice dungeons very fun at the higher levels. They end up being truly challenging and perhaps the most challenging content in all of the souls series. Unfortunately, when people do the first few - they get bored because you are overpowered for the dungeons you enter and most will never see the ones that are actually exciting and difficult. I enjoy the gameplay of Bloodborne enough to occasionally go back and do a few new variants of the dungeons.
