My Kraken build has always worked for me:
Stage 1: 2 Vortex, 1 Banshee Mines (mainly for buying time for Stage 2)
Stage 2: 3 Aftershock, 2 Vortex, 1 Banshee Mines
Stage 3: 3 Lightning Strike, 3 Aftershock, 2 Vortex, 1 Banshee Mines
At stage 2, you can use Vortex and Banshee Mines to control the hunters (you can Vortex them into a wall, for example) after which you can use Aftershock and melee attacks to burst them down. I like to alternate between melee and ranged combat with this build.
You can do the same thing at Stage 3, but with more options because of Lightning Strike (which usually results in a lot of damage or jetpack fuel burned).
Edit: so basically my build is the same as taskforcem85’s.