Jacklight is capable if creating globes of light that grow as they fly, then stop in mid-air at planned areas. The orbs have a space-warping effect, some causing accelerating motions in the general area this can extend into certain types of energy as well.
The area that the orbs affect may be based on their size. Regardless the orbs are restricted in the area they effect. Further he did not showcase the ability to distinguished between allied and adverserial targets.
During the assault on the Teeth, he used his power to disrupt and redirect the Spree duplicates. When Citrine gave the order, he tried to use his power on Butcher only for Butcher to teleport away before he could do any real damage.
When Skitter and Bitch returned and told them of the plan's success, Jacklight slumped over in relief.
↑Jacklight, with a deep royal purple dress shirt and pocket square, his mask a grinning visage that would be fitting for a child’s jack-in-the-box; - Excerpt from Interlude 21.y
↑Jacklight was launching forth the miniscule orbs of light, each growing as it traveled before stopping in mid-air. Each warped space around it, accelerated movement, enhanced the output of certain forms of energy. Where one of his lights was set next to a wall, it redirected one running duplicate into a wall. Another, closer to the ground, swung a Spree that stepped over it into the ground face first.far. - Excerpt from Imago 21.6
↑Jacklight Creates orbs of light that redirect movement in immediate vicinity The Ambassadors - ParahumanList, Bolded edit by Wildbow
I already knew which power she was using next. Imp had sabotaged the gun, jamming the ammo feed, but she hadn’t been able to get at the bow. It was massive when fully unfolded, nearly six feet long, not counting the extra length as part of the curve. Large enough that it required superhuman strength to draw.
Less than a year ago, Butcher had been known as Quarrel, and as Tattletale told it, Quarrel had used a much smaller version of that same bow to kill Butcher Thirteen in a drawn-out fight in New York.
Regent wasn’t in fighting shape. My bugs weren’t able to move fast enough to reach her. Ligeia wasn’t in a position to hit her with water, and Jacklight’s orbs didn’t reach nearly that far. - Excerpt from Imago 21.6
↑It took her a second each time she switched from creating water to drawing it in. Clones slipped through the gaps in the defensive line as she changed gears.
“Rachel!” I gave the order. Before Jacklight’s power makes it impossible to go further or more slip through.
Her responding whistle cut through the night. Bentley and three more dogs were released, charging forward, leaping over our defensive line to crash into a sea of duplicates. The duplicates were now too closely packed together to even fall down, and were literally climbing over top of one another. The dogs stumbled or slipped as the Jacklights tugged at one or two of their legs, then proceeded to tear their way through the crowd.far. - Excerpt from Imago 21.6