I would say you should be level 50+. You could be lower but with better food.
A quest walkthrough for Demon Slayer can be found here: www.runescape.wikia.com/wiki/Demon Slayer
If this is part of the Demon Slayer quest, then the link below should direct you to your answer.
look on runehq
By doing Demon slayer quest
by magic
The Sword you used to kill the demon with, the sword is good against demons.
unless you want to die...NO!
erm your supposed to kill Elvarg which is lvl 80+, close to a lesser demon which is also about the same level In melzars maze you have to kill a lesser demon to open a door for a map piece.
you need at least a mithril armour to prevent dark wizards to attack you. With silverlight , you can kill it by 1 shot. (silverlight is weakness to any demon , including the demon you have to kill in mezler maze when you do dragon slayer.)
ofcaurse he or she can level 60tys can heck i can and im level54
in the deep wilderness against greater demon level 92
I would say you should be level 50+. You could be lower but with better food.
A quest walkthrough for Demon Slayer can be found here: www.runescape.wikia.com/wiki/Demon Slayer
Lesser demon: 85 Greater demon: 97 Revenant demon: 150-250 Black demon: 167 Abyssal demon: 87
If this is part of the Demon Slayer quest, then the link below should direct you to your answer.
Humans can't kill a demon