This is a build I use for farming the pillars in Deimos, Survival missions, easy interception, defense, etc. It works well for any mission type where you can camp out in an area for a little while. Even with 0 forma on the build, this will allow you to easily clear through steel path or any other content you might need to get through.

You can use any arcanes you want, none are necessary. I tend to run with energize and [Guardian].

The low strength is to ensure that vortex doesn't kill things as it sucks them in and holds them in place primarily for Deimos, but it doesn't negatively impact the build in other areas.

To start you throw out a spectorage with the [Spectrosiphon] augment. With maxed range this gives you a very wide area in which kills will give energy orbs. Once that is down, start tossing out vortexes, leveraging the [Repelling Bastille] mod to stack and build up the duration of the pull. Once this is in place you are pretty well set up for constant energy orbs to keep refreshing / extending the vortex and to toss out a spectorage any time it's getting ready to expire.

My favorite weapon to use with this is a heavy attack Stropha, but it can work well with any area / multi-hit type weapon. Stand near your vortex and heavy attack / shoot into the middle of the ball of rag-dolled enemies to get very fast kills and just relish the carnage.