"BOOM!" Achievement

[Fawkzi]

Is there an easy way to get this? The fire seems to last about two seconds and doesn't do enough damage to kill those trapped in it. I thought maybe because I was playing on hard that might be why so I dropped it down to easy but still the same result. The enemies just don't seem to die from fire this way yet the achievement specifically says to kill 30 people by shooting a fire arrow at an oil jar.

I make sure they are right up next to it when I shoot the jar but they sruvive. We're talking level 20 enemies here too.

[PT-Desu]

I just used my hunter bow, when i didnt had any fire around i just equiped my torched and dropped it so i could light the arrow on fire.
I also used to pick up the oil jars and place seveal of them around sleeping guards , step back and set them on fire.

Having that extra fire damage helps as well as doing this in lower level areas.

[Fawkzi]

Worked like a charm, thank you. That achievement was bugging the hell out of me.