Waterfiends
The best monster to kill in Runescape would be the King Black Dragon.
Easiest monster in Runescape would have to be a rat, man, or goblin. If you want something that is easy to kill that gives good experience that would be rock crabs which are member only. They are located up in Rellekka.
lets, see. My best suggestion is druids which are located in the edgeville tunnel
Lvl 28. Delrith.
That would be a goblin.
At that level, you might kill cows and chickens.
At your level, I would say killing Experiments ( Level 25 - 100Hp = 400exp per kill ) near Canfis.
Kill Fire Giants at Baxtorian Falls ( Members ) You can train yourself anywhere as long as there is a monster to kill.
If you run away the monster will disappear ,but when you come back and do whatever the treasure trail asks you to do, the monster will reappear. So yes you can kill the monster later but it will have full life points.
Giants of any kind. Giants of any kind.
For drops, RuneScape doesn't count how many of each monster you kill. Instead, every time you kill a certain monster, there is a random chance of getting a drop. For some items, the chance (the probability) is greater, for some it is less.
in the deep wilderness against greater demon level 92