With [Growing Power] and pax bolt you can achieve a temporary 269% power strength, which translates to 94% slow. (Cap is 95%).
At 175% efficiency, you will be able to sustain gloom infinitely in any mission.
With a good 175% range on gloom, most enemies within attack range will be frozen, otherwise they are too far to hit at you with any accuracy.
You can [Protect] a target easily just by "parking" your Sevagoth beside the target, while you kill with your shadow.
Sevagoth's Shadow: https://overframe.gg/build/153197
Shadow Claws: https://overframe.gg/build/153190