Infused and Abused

Throughout Argus there are lightning storm tornadoes. Stepping in one gives you a 30 second debuff that reduces your health by 25%, and does ticking fire damage to mobs that attack you. The debuff lasts 30 seconds, and within those 30 seconds you need to kill 10 mobs.

I personally suggest you use the area my character is in on this map. The blue line represents the pathing of the particular tornado I used, whereas right where I'm standing are several groups of tiny elemental adds with about ~450k health a pop, all who count towards this achieve.

Walked into the tornado, waited a few seconds to receive the debuff, mounted and went down the hill, grouped up 2 packs of these mobs and blood boiled twice., and that was it.

FrostyShot#1667 if you have questions. (US Servers)

If you get the Lightforged Warframe from the Vindicaar. This becomes a really easy achievement, regardless of where the tornado is. Use it after you get struck by the debuff, then getting the kills with the Warframe will count for the achievement.

Okay, good spot located in Antoran wastes at 52.9 42.7. There's fel river, tornado periodically comes from lake (You can switch realms to find it faster).
Stay nearby to get struck with a fel lightning, but dont get into tornado as it kills you immediately. As you got debuff, cross the river, there's the area named Scavenger's Boneyard.
There are many mobs that have small hp pool (around 1.5kk). Pull a big pack and aoe them down.

Also good spot can be found in Krokuun 42.4 72.5, but there are some elites, so try Antoran wastes.

Infused and Abused short video - https://www.youtube.com/watch?v=WBudgUkgkDI