Frog is the summation of Tsuyu's many frog-related abilities.
This includes great leg strength, wall clinging, a powerful extending tongue, camouflaging and fast swimming. Tsuyu is seemingly capable of using all those skills limitlessly and in combination with one another. She also appears to have access to all abilities used by frogs, regardless of breed.
As frogs are cold-blooded creatures, Tsuyu is highly sensitive to the cold, with prolonged exposure preventing her Quirk from being used while additionally making her feel drowsy and lethargic. Exposure to sudden cold puts Tsuyu into a hibernation-like state, rendering her completely unable to do anything until she warms up.
When Tsuyu was younger, she used to have a small tail, resembling that of a tadpole's. This implies that users of the Quirk are required to go through a short metamorphosis process before reaching their full Frog form.
With Frog, Tsuyu excels in aquatic environments, since her frog anatomy lets her move freely through water without losing strength or agility like most people. She's proficient in fighting and/or rescuing victims underwater, making her very useful for missions taking place in such situations. Despite frogs being freshwater creatures, Tsuyu does not appear to have any problems acting in saltwater.
In spite of her swimming specialty, Tsuyu is more than agile and acrobatic on land too, as she can leap very high and cling to walls. While Tsuyu walks like a normal person just fine, she has never been shown running, instead hopping on all fours like a typical frog. When stuck to some vertical surface, she moves around by crawling.
Tsuyu makes great use of her tongue to reach faraway objects or rescue those in danger, as it is able to extend quickly and very far. Her tongue is strong enough to carry a person and launch them a fair distance. Tsuyu can also swing it fast enough to use as a whip.
The following is a summary of Tsuyu's abilities and features granted by her Frog Quirk:
- An extremely long tongue that can be used to grasp onto objects and people.
- An ability to grip a variety of different surfaces, including tightropes and walls.
- Tsuyu is able to swim well and thus navigate water environments with particular ease.
- Tsuyu's stomach is capable of inflating, which allows her to secrete an irritating toxin contained in the walls of her stomach. Tsuyu can also use her stomach to store items she swallows, regurgitating them if necessary.
- Tsuyu can produce a mucus on her arms that has a distinctive scent, which can be used to confuse foes that rely on smell.
- Cold temperatures can fatigue Tsuyu to the point of forced hibernation.
- She can Camouflage with her surroundings, to a certain degree.
- Camouflage (
保 護 色Hogoshoku?): Tsuyu can change the coloring of her body to match with the surrounding environment, allowing for sneak attacks. However, she is still noticeable to those who could see her and were paying attention. 
- This Quirk appears to be hugely inspired by the superpowers of X-Men character Toad, a mutant and recurring villain in the series. Ironically, whereas Toad is mostly seen as a joke, Tsuyu's abilities are often commended as extremely reliable and practical.
- In addition, the basic premise of the Quirk (doing whatever a frog can) may be inspired by Marvel Comics superhero Spider-Man, who "Does whatever a spider can".
- Due to their frog-like appearances, it is likely that the other members of Tsuyu's family share this Quirk but this has not been confirmed yet.
- ↑ My Hero Academia Manga and Anime: Chapter 14 and Episode 10.
- ↑ My Hero Academia Manga: Chapter 122.
- ↑ 3.0 3.1 My Hero Academia Anime: Episode 55.
- ↑ 4.0 4.1 4.2 My Hero Academia Manga and Anime: Chapter 15 and Episode 10.
- ↑ 5.0 5.1 My Hero Academia Manga: Chapter 196.
- ↑ My Hero Academia Manga and Anime: Chapter 66 and Episode 36.
- ↑ My Hero Academia Manga: Chapter 113 (p. 7).
- ↑ My Hero Academia Manga: Chapter 195 (p. 11).
- Frog - Wikipedia article about the animal this Quirk's abilities are based on.
- Toad (comics) - Wikipedia article about the character that most likely inspired this Quirk.