I was fighting diablos yesterday for the first time, his movements and attacks are almost identical to the monoblos and i've already killed monoblos twice so that wasn't hard for me, but to my surprise the diablos have incredbily hard shells and the only place where i can hit him with and not bounce is his legs. Its often too risky to jump near his legs and attack, mainly because he will either do his tailwhip or my weapon will bounce if i didn't aim it perfectly at the leg. I also can't cut off his tail to stop him using the tailwhip because the tail will bounce my weapon off as well.

So would my weapons not bounce if it had blue sharpness or do i need to get ESP for that?

So dude. Diablos is faster than monoblos. You have two choices for killing him if you are a beginner.

You can use a Great sword and sonic bomb. When he goes under the earth, use a sonic bomb. He will be trapped and you can also hit him. You can't use sonic bomb when the Diablos is in fury.

You can make sonic bomb with gunpowder and screamer.

Or, use a bow or a bowgun with clust, pierce and pellet ammo. You shoot and you run xD.

I think using Great sword is better.

Ouais simpa le site, dommage que les dessins soient fait paint et que sa soit en anglais, mais c assez réussit. Personnellement jsuis juste venu faire un pti coucou pck le + gros ennemi ke g du battre c le congalala ^^. Bloqué au céphadrome!