if your asking a question about what you need to fight something, it's always a good idea to say what your stats are, but as for how to kill dark beasts, i have no idea.
whip price is accurate, and in my opinion is the best weapon in game, unless your solely training strength, then a d long/scimmy or a sara sword is the best option. and rune is cheap.
a good way is to get limestone, and meltify it in a furnace, then use a chisel with it, takes away 8 damage from chiseling it, and 8 from meltifying it. thats worked for me before, but right outside the ogre enclave, you can steal rock cakes.
two people in this thread's siggies say theyre tipits best fog player lol. but on topic, just change all your recovery questions and your password to something random, or something your cousin would never guess. and if he still manages to hack it somehow, tell his mommy.
but green dragons are also much much quicker, you use less food, and if you can use a bull ant/terrorbird, you can last a long time in the wild (lvl 13 north of goblin village) i used to kill them there all the time.
I don't think they nerfed it. About 1:1 ratio from kills to bars. it used to be 4 bars basically every kill. so it was more of a 4:1 ratio of bars to kills.
get 40 summoning for a bull ant, they make it so you can run for a long long time, and the pouches/scrolls are cheap. 40 summoning really isnt too hard to get either.