What is an effective way of acquiring the Demolition Derby achievement?

Cemetery of the Forsaken is a pretty nice place with relatively few enemies. Just go around in a circle, keep your rhythm, and don't forget you can smash those stone column things near stairs. Use those columns to hop between the gravestone patches.

Also, having a skill such as Leap or some other kind of teleport will help you keep the rhythm if you accidentally end up too far away from your next target.

I recommend using a close-range melee attack. AoE attacks are not recommended because you might end up in an empty area that you created. If you use skills that consume your resource, make sure you have as much as possible and can easily regenerate it by, for example, attacking the skeletons in the area.

Using +movement speed gear is also very helpful.

I found royal crypts to be much easier with all of the ash pots. I failed at around 20 items and still ended up with a 63 streak.

To get this achievement, I recommend to use a Demon Huntress with the Skills:

• Elemental Arrow, Rune Ball Lightning.
• Vault
• Preparation

Go to the Forsaken Cemetary and use your Ball Lightning. The Lightning travels rather slow, spreading the destruction of the tombstones and other destructible over a considerable amount of time. Move around the cemetary quickly using Vault and set of Balls of Lightning in different positions around the central pavillon. This should very easily generate this achievement.

Another Option is to go to the Royal Crypts and run through it using Ball Lightning as you run/vault. It took me 1 try with the above method.

Narrow hallways & 12+% Run speed boots are the key to success.