Kefla's powers and abilities
Anime
According to Vados, Kefla's power consists of Caulifla and Kale's power combined to their respective absolute peak, and then multiplied tens of times. When she is first born, Kefla herself says she feels infinite power bubbling inside of her, and Goku remarks that her power is so high that he cannot sense a limit to it. Vegeta also notices Kefla's strength during his fight with Toppo, saying that he felt "an incredible energy". On the sidelines, Kefla's power was enough to make even Jiren twitch during his meditation.
After Kefla is formed Champa states that she is Universe 6's true trump card. When attacking Super Saiyan God Goku, Kefla moved so fast that Goku did not notice her movements until after she appeared behind him. During a brief scuffle, Kefla easily shrugged off Super Saiyan God Goku's attacks, calling them "lame", before easily slamming Goku to the ground. Though Goku was still tired from his fight with Jiren during the entirety of his battle with Kefla.
When transforming into a Super Saiyan, her power is enough to force Goku to go Super Saiyan Blue, and Champa also notes that he did not expect that Kefla's energy as a Super Saiyan would be so high, while Whis notes her power to be "terrifying", though Vados is not sure if she could defeat Super Saiyan Blue Goku where he at his full power, Champa believes she can win due to his lack of stamina. Super Saiyan Blue Goku and Super Saiyan Kefla then go on to fight evenly, Goku then goes Super Saiyan Blue Kaio-ken in an attempt to defeat Kefla - with a clean blow from him severely damaging her and causing the spectators to believe she may be down. However Kefla goes beyond her limit and gets back up. At this stage it is noted that he only has enough energy left for one more attack - which misses, Kefla was then able to knock him out of his Super Saiyan Blue Kaio-ken state with a single kick to the neck, when she attacked him from behind while he was firing his attack. Kefla finds it unfortunate that she was not able to fight Goku for longer and prepares to knock him off. Once the tired Goku activated Ultra Instinct -Sign- a second time, Whis stated that her power as Super Saiyan rivaled that of the Spirit Bomb, which is what allowed Goku to re-take his Ultra Instinct -Sign- form.
When powering up to Super Saiyan 2, Kefla's ki rivaled that of the tired Goku's Ultra Instinct -Sign- state in pressure and size, which destroyed the arena around her and sent people flying away. Piccolo also states that she may have surpassed Goku's "earlier level"; referring to Goku's first usage of Ultra Instinct -Sign-. Kefla claimed she could destroy an entire universe with a single shot with her immense power, Vados also states that while Kefla's attacks are very strong and fast, Goku's reflexes are still superior. In this stage, she could block a punch from Ultra Instinct -Sign- Goku, but was unable to avoid a barrage of solid hits. Once feeling pressured, Kefla was able to intensify her power further - awakening an "unpleasant power", generating an onslaught of ki blasts and lightning bolts that covered most of the arena. Her ki control in this form is also very refined, able to control the path of her blasts and bolts to track Goku, which ultimately allowed her to nick his arm and cut some hair, which shocked everyone. Her energy was so strong that Roshi stated that if one of the blasts were to hit Goku, not even he would survive. However, even with her advantage in raw power, she was still unable to hit Goku in his Ultra Instinct -Sign- form as he unconsciously dodged, evaded and countered almost all of Kefla's attacks - even her last-ditch, final attack, using the Imperfect Instinct Kamehameha, which broke her Potara Earrings - defusing her - and threw her out of the arena.
Manga
When fused from Caulifla and the previously power stressed Kale, Super Saiyan Kefla is said to be as strong as Kale - but with the added bonus of having Caulifla's fighting skill. She is able to easily overwhelm every member of Team Universe 11 at once (aside from Jiren and Toppo) despite them being known for their incredible teamwork. Vados notes that Kefla may be unmatched in the Tournament of Power, indicating she is the strongest member of Team Universe 6. Jiren has no interest in Kefla and thinks fighting her is unnecessary. Ultimate Gohan is able to easily deflect a charged energy wave from Kefla. Ultimately, the Saiyan-hybrid proved Kefla's equal as the two battled with a vicious exchange that left both battered and ultimately scored a double elimination between them.
Techniques and Special Abilities
Flight - Kefla can fly by utilizing ki.
Ki Blast - The most basic form of energy attacks.
Continuous Energy Bullets - A combination of many energy waves fired at a very rapid rate.
Fist Cannonball - Kefla gathers energy in her fist, then fires a concentrated blast of green ki at her opponent. Super Saiyan Kefla's ultimate attack in Super Dragon Ball Heroes.
Gigantic Blast - Kefla creates a cluster of green or red Ki blasts in both hands (up to five in each hand) and fires them at her opponent. With her precise Ki control, she can also have them home in on her opponent.
Gigantic Burst - While using Ray Blast, Kefla charges a much powerful Gigantic Blast and fires it at her opponent. When charging it, the energy spheres mix up forming a spinning disc of Ki in each hand.
Ray Burst - Kefla releases her aura strongly enough that fires powerful laser-like flashes omnidirectionally.
Kiai - Kefla throws jab-like punches at her opponent in rapid succession, which causes thin, wind-like punches to appear on impact behind the opponent.
Transformations
Super Saiyan - Kefla's Super Saiyan form takes on the nature of Kale's powers. She appears as a stabilized Legendary Super Saiyan, gaining a slight increase in muscle mass and noticeable increase definition while growing noticeably taller, almost as tall as Goku. Her hair springs free from its ponytail and sticks out in while turning bright green. Her eyes also become bright green and, uniquely for a Saiyan in a transformed state, her eyes become wider.
In the anime, Kefla assumes this form in order to combat Super Saiyan Blue Goku and manages to fight an even battle with him. Her ki attacks forced Goku to use Super Saiyan Blue Kaio-ken, even defeating the Saiyan after a surprised attack. However, she is pushed back when Goku once again acquires his Ultra Instinct -Sign- state. It is speculated by Whis that Kefla's power in this form rivaled the Spirit Bomb that caused Goku to break his limits and enter Ultra Instinct.
In the manga, due to fusing when both the fusees are in Super Saiyan form, she is permanently stuck in this state and could not power down to base form during this merger's time frame. Unlike Kale she does not progress into a Power Stressed state as time goes on - due to the control granted by Caulifla. She is said by Vados to be as strong as Kale, with the fighting skill of Caulifla.
Super Saiyan 2 - In the anime, like Caulifla, Kefla possess the Super Saiyan 2 form, but with a similar appearance to Kale's Super Saiyan 2, though with the natural addition of frequent and wild bio-electricity discharges. When Goku takes on his Ultra Instinct -Sign- state, Kefla responds by becoming a Super Saiyan 2. For as powerful as her Super Saiyan 2 form is, she is still unable to land any hits on Goku.
When cornered by Goku, Kefla went through a fight or flight response and awakened a new unpleasant power, which Vados referred to as her "final weapon", and she became surrounded by ki that fired in all directions and was fast enough to graze Goku with her attacks. Master Roshi even remarked that even Goku couldn't survive taking one of these attacks head on. When using this power, her hair changed to a darker green color. However, she is defeated, as Goku dodged almost all of her attacks, no matter how swift and powerful they were.